There is a blog on Wordpress. How to make a theme out of it?

Question

Blogs

Good evening!
Can you please tell me how to make a Wordpress theme? Not from scratch, but from a finished site. I have a blog with a slightly modified default theme installed + many plugins added + heavily modified css.
Question - if I have a clean WordPress installed on a new hosting, can I just upload a folder with this theme and everything will be installed like on the old blog? Or one folder is not enough and you need to upload a database file, etc. Then how do they sell individual themes? there seems to be no plugins in the template and no database file.
If there is any informative article on this topic, please click.

Answer 1

a little strange question, take plugins, a modified theme with css and install it all, activate it and be happy.