When you wrtie for example 'mike's mission', notice how there is an apostrophe after 'mike', now what about with regard to 'its' as in 'its jaws were huge' howcome we don't put an apostrophe after 'it'?!

The apostrophe has more than one function.

It can indicate possession, as in "Mike's hat."

It can indicate the omission of letters, as in "don't" (do not).

When used with "it," the apostrophe indicates the omission of letters (it's = it is).

The possessive form of "it" is "its." Like "his," "her," and "whose," "it" does not take an apostrophe to indicate possession.

Is that clear?
Yes thanks