What languages should i master if i want to. be a good web and mobile app developer

Question

deciding which language to choose

Answer 1

To be a web developer you need to know Html,css and javascript. you start with html,then css and then js and when you masterd it you can combine sql,php and more stuff.

To be a mobile app developer you can learn java,c# and more, there is many languages for mobile development,xamarin is one of them and is working like c# but with diffrent classes.