(It’s, its) definitely going to rain today.

It's

Explanation:

It actually can be both but if you want better posture I prefer it's but if your in a conversation with your friend it doesn't really matter

It's

Explanation:

It's is a contraction of “it is” or “it has.” Its is a possessive determiner we use to say that something belongs to or refers to something. But the rules are very clear... it's is the same type of contraction as “where's” or “there's,” and its is a possessive just like “my” or “your.”

answer: this is easy, i found "it"

i will repeat the question again, "find it."

here, i located it.

i've read it so how can i ?