I want to make a web,app which language i learn ?

Answer 1

A variety of tech stack can be used to build web app.

Here is Fireship's quick demo of web app using 10 different languages:
https://youtu.be/FQPlEnKav48

Answer 2

this trio in same order

- https://www.sololearn.com/Course/HTML/?ref=app

- https://www.sololearn.com/Course/CSS/?ref=app

- https://www.sololearn.com/Course/JAVASCRIPT/?ref=app