Whenever I study I forget everything I studied for the next day. What the hell am I supposed to do?

I study a lot then the next day I forget everything, and I lost motivation to study, my finals exam are next week and each one is after the other so I have no time to study each subject for 1 day. This is hell, I cant even take a break! Each subject has 10 lessons, and every lesson takes an hour. My brain can’t comprehend it!