I am 13 years old I have recently found out about shemales and they turn me on and they started to get to think that maybe I can be one when I grow up what do you think I should do?

Okay slow your roll, buckaroo.
Transgender people do not appreciate the term shemale. Never use it.
Secondly, if you really think you would be happier as a girl, pursue that. But it sounds like you found redtube and want to jack it to trans people. Know that many trans people are kicked out by their families and turn to sex work as a means of income. But still, your turn ons are yours, so use discretion.