Long story very short I need to know. How much damage of each damage types would a creature take if they were hit by ever damage dealing spell at the same time. 

If only there was a way for you to look up spells and find out yourself. Oh wait. There is. https://www.dndbeyond.com/spells

Google has a free spreadsheet app you can use for tracking.

Enjoy.

"Every damaging spell" = infinite.  People are creating new spells every day.rr

So your first thing to do is to limit the spells from every to something like 'every spell in the PHB', or 'every spell in the WoTC non-world specific books', or 'every spell in WoTC books', etc.

There are no negative HP, so I think they would only take as much damage as their total HP. For example, it wouldn’t matter how many spells you hit a commoner with at the same time, they would only take 4 damage.

Quote from IamSposta >>

There are no negative HP, so I think they would only take as much damage as their total HP. For example, it wouldn’t matter how many spells you hit a commoner with at the same time, they would only take 4 damage.

 I think they might take 35 points of damage from say a fireball but only lose 4 hp. The other spells would just give auto Death Save fails.

Which is actually kind of funny. A single Magic Missile casting can potentially knock a person unconscious then wipe out all of their Death Saves, and a max damage rolled fireball would just knock them out.

I ment officially spells at this moment. 

I don’t care that there will be an ton over kill. I just need numbers

I suggest doing the calculations for yourself. It's unlikely anyone has bothered to do this computation, as there are more than 300 damaging spells in the game and it's not a number most people would care about.

Quote from Nero_sparda >>

I don’t care that there will be an ton over kill. I just need numbers

 
The fact that it would be overkill is not my point. The question on the table is “how much damage [sic] would a creature take?” My point is that the combined total of all the damage rolled for all those spells is irrelevant, a creature can only take a maximum amount of damage equal to its HP. I say this based on a few known facts.

1. Once a creature hits 0 HP, it can’t loose any more. It’s not like in older editions where there were negative HP and you could continue to dammage a downed creature. Once a creature hits 0 HP, damage stops being tracked numerically against that creature.
        While yes technically every creature theoretically does go into death saves upon hitting 0 HP, most people only use those for PCs, all other creatures just die. When a creature dies, it stops being “a creature,” and instead becomes at best “a corpse/body,” or otherwise is counted as “an object.”
        Even if one does consider death saves for all creatures, or we specifically want to consider this scenario in regards to a PC, once that creature is in death saves damage is still no longer tallied up, any “hit” causes a failed death save and a “critical hit” causes 2. There is no actual “damage” dealt or tracked any more at that point.
2. It is well understood that the amount of damage that gets rolled doesn’t necessarily equate to the amount of damage a creature actually takes. If anyone disputes that fact I simply refer you to the rules for damage resistance and immunity, as well as any one of the many, many instances in the game where the phrase “or half as much damage on a successful save” appears to prove this is true.
3. There is prescient that even without any resistance or immunity, and without a successful saving throw, a creature does not always take an amount of damage equal to the amount rolled. There are a number of examples I could cite, but I’ll stick to the one I see most often, vampiric touch. The spell does an amount of damage and the caster regains HP equal to half the damage dealt. If you roll well and hit for 18 damage, a creature would take 18 damage and the caster regains 9 HP. But if the target only has 10 HP, the 18 rolled is irrelevant, the creature only takes 10 damage, and the caster therefore only regains 5 HP.

Now to answer your stated question of “how much damage [sic] would a creature take?” The most accurate and honest answer I believe that anyone can actually provide you at this point is, that you have not provided enough information to give you a real answer. To properly answer your question, I must first ask one of you: which creature?

Quote from IamSposta >>

 which creature?

 This is actually very important.

Residences, Immunities, what kind of bonuses do they have for saves, whether they make the save or not, where are they located (in the air, on the ground, underwater?)

Additionally, is it just one casting of each damaging spell? How do you get that many casters to draw line of sight to the target? Are the spells being cast at base level or are they being up-cast?

Quote from Pantagruel666 >>

I suggest doing the calculations for yourself. It's unlikely anyone has bothered to do this computation, as there are more than 300 damaging spells in the game and it's not a number most people would care about.

 
Yeah, I mean it sure sounds like the OP feels entitled to having other people do pointless labor for them. I hope I'm wrong.

Also an issue of what to do about spells that have multiple possible damage types like Chromatic Orb, Chaos Bolt, Destructive Wave, Spirit Guardians, Prismatic Spray, Prismatic Wall, Glyph of Warding... and more. These spells either have a choice of damage, random damage, or do multiple at once. How do you handle these? Consider the spell cast multiple times getting every damage type once? But then what of something like Destructive Wave - if you cast it twice you get to choose one for radiant and one necrotic but both would deal thunder which seems to defeat the point of your question.

I'm the kind of dullard who likes spreadsheets and running through the lists to check stuff (specially since most time I'm not able to do much else) but there's too many variables and what-ifs and confusion to consider even if I did have the mental stamina for this. Add to that Sposta's very valid point about how damage works and the importance of who the target is... There's too many complications. 

Add the entire lack of interest in knowing and ... Yeah. 

As I said, in post 2 - you have the spell list. You should probably find out yourself using whatever rulings you want. 

Less entitled and more hopping someone would find the question interesting think “hmm I wounder what it would be” and do it so I didn’t have to. Don’t got any of the books. Best I got is hopping 5e companion is accurate 

Id say if there are different possible elements maybe they could be put into there own category

I don’t got the time. Knowledge. Skill or patience to do this on my own. Was hopping one of y’all just had an answer or was willing to find it for me. But in the end. Should have lost hope before I got it. No clue why I ever get hopefull on things. I always end up disappointed 

But anyways. If any of y’all know someone who would do this or a thing here who may have someone who would please do tell. And if ya wana know where this question came from. The lore behind it. Feel free to ask

Quote from Nero_sparda >>

I don’t got the time. Knowledge. Skill or patience to do this on my own. Was hopping one of y’all just had an answer or was willing to find it for me. But in the end. Should have lost hope before I got it. No clue why I ever get hopefull on things. I always end up disappointed 

 
Hope is never pointless if one expectations are reasonable. But consider this: you say “I don’t got the time. Knowledge. Skill or patience to do this on my own.” Pray tell, what gives you the impression any of us do, especially given that none of us is interested to learn the answer to a seemingly irrelevant question?

Lemme ask ya sumpin.’ Why are you seeking the answer? Is it related to something in a campaign? Is it for a contest or a wager? Are you under threat of unfortunate consequences if you don’t produce the answer? Is it just idle curiosity? Please tell me. Why do you ask?

Quote from Nero_sparda >>

But anyways. If any of y’all know someone who would do this or a thing here who may have someone who would please do tell. And if ya wana know where this question came from. The lore behind it. Feel free to ask

 
I already asked while you were making this post.

Ya see me one horned friend it all started one late night. I came up with the idea for this character. And skipping most of the character he has wild magic. So I came up with the idea of 3 tables of wild magic. With the first one if ya get a 100 ya move up to the second one. With the second one ya move to the third. And the third I would roll 2d10 the second one only coming in play if the first is a 10 and if the second one is a 10 aswell this was the idea. Just something stupid I thought of while tired and thinking of character ideas. And I was hoppin someone out there had the same question one day and just had the answer. Never expected almost anyone to care about it

Sorry for the wall of text lol