Is there no samsung dex mode for samsung F 62?

Something random and so unexpected happened that i could'nt believe it.....Earlier i talked about how i did not have the wifi calling option....then i guess in hours the option appeared and then dissapeared in a day.....What do you think is it possib...

Is there any option like wifi calling in samsung mobiles cuz i cannot find it....i think after the recent update the option is removed

I am a student, and i have 2gb and i use unacademy for my lessons. This device uses the data very fast and but i have to classes for almost 5 hrs. So how can i decrease my data usage on unacademy itself???