Huawei cell phone crashes every time?

I own a Huawei Mate20 lite and have a little problem: My phone freezes whenever I use apps, or the apps crash and I can't open them again before I restart my phone. I really don't feel like it anymore. The settings also do not work properly. I can't set a password. The phone just won't work. (I have a lot of apps on the phone) Does anyone have a solution how I could fix this?

Free up memory

Sorry but that doesn't quite work