I don’t know exactly what I have to say while doing my wudu before prayers (i’m not an arabic speaker yet). Is my wudu still valid if I don’t say nothing while doing it ?
Also do you have a book or websites where I could learn it to properly to it?

You don’t need to say anything whilst doing Wudu. It’s not obligatory to say anything. It’s recommended to remember Allah and recite Duas

This video shows you how to perform Wudu