I don`t know.
Because i don`t have unifome.  = I don't know yet because I don't have a uniform.

and i wearing a unifome is litte after
Because i am not middle shcool studen t. = I'm going to wear a uniform when I reach middle school.

3month after is i am a middle shcool student. we have unifoms. = Three months later, I'll become a middle school student and I'm going to need a uniform.

I have only p.e. class unifoms. = I only have P.E. class uniform right now.

So this homework is 3 month after. = This homework will be answered after three months.

You will give this homework at 3 monfh after. Ok? = Will you give me this homework after three months?

what are you think. = What do you think?

my idea is that. = This is my idea.

NOTE: Sure! I'll give this homework to you after 3 months. ;)