Studies for a 15 year old

My brother and me are moving to Portugal this year. How difficult would it be to start in a new school, he understands and speaks a little portuguese, but he doesn't know how to write. Also, he doesn't know any history or geography portuguese. Are they going to make him an admission aplication?
Is there anyne here that have already done this process?
Thanks for your help!

PD: He speaks spanish

New topic