Im about the start a new campaign and wanted to try my hand at a cleric. But I was curious the the amout of support, health, and buff spells if a cleric with low wisdom is passable as the levels increase?

So far im planning a half-orc with either War or Forge domain for backstory flavor. I know our party will have a Bard (unknown college) and at least one other. I was planning my orc to have mainly Str with Con stats next with wisom sitting around 12-14 with spell focus on buffs and healing. 

Id prefer to not be another class for backstory and campaign setting reasons.

You do not need to meet the class requirement when you create your character, so even an 8 in wisdom would allow for your cleric build, but.....if you ever want to multiclass your cleric, you will need to raise your wisdom to at least 13. 

PHB page 163: "To qualify for a new class you must meet the ability score prerequisites for both your current class and your new one....

To answer your question about viability it could work since the cleric spell list does have quite a few buff spells that don't care about your wisdom score. That said, you will lose out on some of the better cleric spells effectiveness, eg spirit guardians will be less effective only dealing half damage, spiritual weapon will be less likely to hit, etc... And if you don't multiclass to a class with extra attack, your one attack every round will quickly fall off in effectiveness, especially once martial players get extra attack and start tacking on feats. 

You can actually get by with a low spell casting ability on most spell casters, but as ElSpivo says you'll be cutting off some of your spell list, or at least making those spells substantially less effective, so you probably won't want to take them. That said, Clerics are casters who can swap out spells on any long rest, so you're not stuck with them at least.

It means you won't have much in the way of damaging cantrip options, since they're all attack roll or saving throw based, which is determined by your casting modifier. But Guidance, Light and Mending, are all really useful non-combat cantrips. For spells you can still take healing spells, plus classics such as Bless, some out of combat spells like Detect Magic and so-on.

Basically it means you won't likely be doing your combat damage with spells, which means you'll want to lean into the party support roll and/or tanking (taking damage to keep enemies on you rather than others). Forge Domain does give you Searing Smite which can boost your one attack per turn, and Heat Metal is very situational but fantastic when you can use it (solid damage, no save and only requires a bonus action), though they'll both struggle if an enemy is resistant (or even immune) to fire. If you don't mind necromancy you could try a bit of Animate Dead from 5th level to throw chaff at enemies?

Really though the question maybe is how much Constitution do you think you'll need? If you start with +2 or +3 in Constitution then focus your score increases on Strength and Wisdom you can still get them both pretty high, especially if you're willing to take a negative modifier on some other abilities (Charisma and/or Intelligence?).

Anything's possible. Heck, if you're doing the point-buy system, then you could start your half orc cleric with stats of: S 16, D 12, C 14, I 10, W 14, Ch 10. Or even S 16, D 10, C 16, I 8, W 14, Ch 10. (That's with the racial modifiers factored in.) If you use your 4th level ASI to boost your Wisdom to 16, then you're fine. You can use the rest of your ASIs to boost Con and Str and some feats - probably War Caster and Tough. That's fine. Sure, some of your healing spells may heal for one or two hp less than what would be ideal, but on the other hand you'll be able to survive more hits and keep yourself up and healing longer. Just pick a domain that gives you heavy armor, equip a shield, and tank the fight. Every hit you take is a hit your teammates don't have to take. It's better to have the bad guy swing at your 20 AC than to be swinging at the wizard's 11 AC. 

In the long run, if you use the second set of numbers I suggested (16 10 16 8 16 10), then by level 20 you've had five ASIs so you'll top out at S 18, D 10, C 18, I 8, W 16, Ch 10. You'll have the feats War Caster and Tough, and you'll have around 223 hp. 

But... that's just a bunch of numbers. Numbers only tell a small part of the story. The important thing is how you role play the character. That's where the real magic happens! Have fun!

It’s totally viable.

Your cure wounds, for example will be a d8+ 1 or 2, instead of 3 or 4. Either one will get someone up from unconscious. Bless will work perfectly. And if it gets to be a problem, just pour your asi into wisdom and you be just fine. 

I have created a low level cleric. She is a Deep Gnome with innate Svifneblin Magic ability.

As a back story she is the daughter of the Deep Gnome cleric, Suntunavick. 

It's....possible. However, just remember that healing on clerics is usually affected by your Wisdom score too, so its...not the best. If it fits your character, then go ahead.

Beyond having low save DCs and attack modifiers with offensive spells and reduced effectiveness of healing spells, a low wisdom score reduces the number of spells you can prepare each day.  That hurts at least as much as any of the other effects.

I've wanted to do this before, but I never actually did. Spells like magic weapon that make you more powerful without depending on your wisdom or that aren't completely useless on a successful save or missed attack.