Im losing my faith in islam

The idea of disbelievers all going to hell seems unfair to me and just unreal like theres so many people in the world, no way all of them will go to hell. Life is very unfair too, i dont believe that some people who have a shitty life will have a “better life” in heaven. Its unfair i mean some people will get both ? I also dont get how everything is already written like whats the point of us living if God already knows what will happen and if youll say “u can change qadr” like doesn’t he already know that ill change it. Idk honestly