Hello, i bought my acer nitro 5 2 years ago and now i have problems with really slow startup, it takes about 4 minutes

And after that, its still slow for 1-2 minutes and after that i finally can use the laptop... the next problem is the overheating while i playing valorant for example, i have 100% cpu usage, about 80C with coolboost.... and when i calling with my friends while playing valorant, they are lagging so much because that f****** 100%cpu usage. I read same problems here and i think the most people with this problem solved it with thermal paste, because default acer thermal paste is trash. I am asking is there some other way how fix it my problems? I disabled many programs from windows on startup, i optimized windows by many guides but its still slow