tell myself that I will get this chance in the future so I have to think of a better way to use it in the future in the meantime.

Give 13 year old me a lifetime supply of HRT

I would tell myself to become girly as a kid

Like in that order? I get to do something now and then cancel it, not go back and fix my life? What a cruel question.
I'd blow all my money (and sell all the stuff I can't carry with me) on a long trip abroad visiting all my long distance friends.

probably tell my young self to ignore school completely and put more effort into learning computer shit

Lotto numbers.

fight french people maybe

bring fusion tech and live off of patent money

my singular change would be to change more company names to be deez nuts jokes
that or secretly make some low rate film sync up to dark side of the moom. although i already think that one happened with paul blart 2

Prevent poor financial decisions

Die, just to figure out how it feels to die, not to actually die.

I'll let you figure out how to use the time machine after i'm ded,