Whenever I sign in minecraft then there is no issue but when I save and quit and come back in minecraft it shows couldn't connect to Realm and Coming soon server . Please solve this bug/issue

I can't play in servers and realm's with cellular data after turning on cellular data in profile settings . It always asks for wifi

i play minecraft but there is black screen issue so i deleted minecraft and all its files and after installing that but after that my miinecraft is running on 1 to 2 frames even on very low settings it uses my dedicated gpu not my integrated gpu