-In dnd if a character drinks ink does he get poised or not?

-I want you use bag of holding to have the inkling hide in it and is it possible for inkling to hide inside poison jar and come out  half covered with deadly poised and go inside character nose or but body's and attack them from inside.

I used the inkling to cover my mouth and nose like a gas mask so I will not breathe the toxic gas yo get poised. 

And I use the inkling to hide in.my bag and attack and hide in the bag

Drinking ink is probably not meant to be poisonous. It is most likely made from soot or a mix of iron sulfate and acid from oak trees. Unpleasant probably, but not dangerous.

The inkling mascot does not have poison resistance/immunity to survive contact poison and does not deal piercing or slashing damage to benefit from injury poison. So any poison soaking shenanigans would not go well.

A nose is usually smaller than 1 inch, so nothing in the inkling's stat block suggests it can do that. The rules don't cover... uh, unwelcome entering of creatures.

Inkling's are not gas masks. If you can't breath ink, you are smothering yourself. (See suffocation rules: https://www.dndbeyond.com/sources/basic-rules/adventuring#Suffocating)

Should probably provoke opportunity attacks as it jumps in and out of the bag.

Quote from Finaldash03 >>

-In dnd if a character drinks ink does he get poised or not?

-I want you use bag of holding to have the inkling hide in it and is it possible for inkling to hide inside poison jar and come out  half covered with deadly poised and go inside character nose or but body's and attack them from inside.

I used the inkling to cover my mouth and nose like a gas mask so I will not breathe the toxic gas yo get poised.

And I use the inkling to hide in.my bag and attack and hide in the bag

You only actually asked 1 rules question, so I'll do my best to clarify your rules mistakes (or things you might have overlooked) here.

1.  No.
2. Several things to cover:
   1. Your inkling doesn't need to sleep, eat, or drink, but it does need to breathe.  It can hold its breath (baseline) for 3 minutes and 12 seconds, after which it will begin dying.  A bag of holding has 10 minutes of breathable air total, so if the mascot is the only creature in the bag, you have 13 minutes and 12 seconds from entry until it begins dying, and then you have another 6 seconds of relative safety during which the mascot can't have failed all 3 death saves yet.  From 3 minutes and 24 seconds onward, your mascot has an exponentially larger chance of being dead.
   2. Your inkling isn't immune to any poisons, so anything you coat it in will immediately affect the inkling, potentially harming it while also "using up" the poison.
   3. While an inkling can fit down the esophagus of most creatures, we have no rules for it to successfully achieve entry - we have rules for it trying to do things while inside based on monsters that have actions to swallow adventurers that your DM can crib, but the closest thing we have to mechanism for getting inside someone is that the DMG has rules for getting onto someone without their consent (similarly to mounting a mount, but with rules to oppose each other).  You'll need a hefty amount of house-ruling to make climbing inside a target a reality.
3. If your inkling blocks your airway you will suffocate and die, as you have no mechanism for breathing the inkling.  If you don't need to breathe, the inkling will neither hurt nor help you when it does this.
4. Tiny creatures can absolutely take total cover inside your equipment as a general rule (note that there are many different sizes which all amount to Tiny, so how much space the creature needs involves consulting with your DM); if you're going to use your inkling to attack, this is on the very short list of credible ways you have to keep it alive long enough to matter.