Using "지마"?
How exactly ?
오지마 , 가지마
I know that they're from 오다 and 가다

하지마 - To stop
오지마 - to not come
가지마 - to not go
Is this shortened or similar to a particle? I tried adding 지마 to 먹다 and translated it and it actually translates "to not eat"
what exactly is it?

Question

Using "지마"?
How exactly ? 
오지마  , 가지마 
I know that they're from   오다 and 가다

하지마 - To stop 
오지마 - to not come
가지마 - to not go
Is this shortened or similar to a particle? I tried adding 지마 to 먹다 and translated it and it actually translates "to not eat"
what exactly is it?

Answer

지마 is not a word or a particle.

하지 마 is compose with
하(다) + 지 + 마
하다 means "to do"
지 is a suffix used for negation or  prohibition and usually followed by " 않다, 못하다, 말다"
마 is an imperative conjugation form of 말다.(말+아 => 마)

하지 마 means "don't do it!"
오지 마 means "don't come!"
가지 마 means "don't go!"
먹지 마 means "don't eat!"

하지 마 is informal imperative 
하지 마요 is a little formal imperative 
하지 마세요. is formal imperative
하지 마십시오. is very formal imperative

먹지 않다 means "to not eat"
먹지 못하다 means "can not eat"

그는 사과를 먹지 못했다
He couldn't eat apple.
그는 사과를 먹지 않았다 
He didn't eat apple.
사과를 먹지 마
Don't eat apple!