Can i write android app with ‌HTML???

Answer 1

Yes by using phonegap

Answer 2

Yes

You can need to write a progressive web app.

lots of Demos here

https://pwa.rocks/

once page loads just click your hotdog menu in the browser, and click "add to home screen"

Now you have icon on your homescreen to launch the web app.

If you want to build your own, here is the tutorial

https://developers.google.com/web/fundamentals/codelabs/your-first-pwapp/