I'm a beginner, i want to be a web developer, from where i start learn to be application builder with python

Answer 1

If you want to program an application with Python you need to learn Python.

For web development, you need to learn html, css and Javascript.

Answer 2

You can host a front end for free with GitHub pages (this will be your HTML/CSS/JavaScript files).

For hosting python on the backend you can use Heroku for a server and FireBase for a database.

There are tons of other options but these should at least get you started. I would recommend making a simple web page with a couple buttons that perform basic CRUD operations.

Don't use any frameworks or libraries to start. Build up your foundational knowledge first and avoid learning too much at once. Keep the project simple and small. Bite sized chunks :)