Hello Dear all who is reading this questionmark which has been on my mind for a long long time.

I´m a 17 year old troubled highschool student, currently in her second year of highschool. My Family is from turkey, but i´ve lived in Europe my entire life basically. Moving around from Netherlands to Germany, Denmark and Norway. (that made me feel.. less like a Turk, more european)
So here comes my question; i really really wanna study in turkey after highschool, but i have no idea how. Like, Is there an specific grade you need to have for each subjects. Be superb in turkish language? What am i supposed  to do? Are the universities hard in turkey?
I´m planning on studying in a international University, since i´ve gone to International schools my entire life, and i´m currently in IB (International Baccalaureate) I know how things work out in Europe, but i´m not so quite sure how it works out in turkey..  

Anyways.. i hope you guys get my point. Anyone who can relate, and can answer my questions?
For those who moved from a foreign country to turkey, how did you guys do? >-<
Please help me out!!