It doesn't depends on your level how good you are in a programming language. From level 15 on you only get the xps from challenges with same questions every time, so don't focus on lvl instead of trying to code some small programs (:
I think you won't really learn to code until you write a program of your own. Come up with a simple idea and work on it. Don't be too ambitious with your project idea. Choose an obtainable one.
If you go through the levels in courses on here that's great but you won't really understand how to code until you write a program of your own.
It totally depends on how long it will take you but probably a couple years or so to become intermediate.
Experienced programmers will tell you that you learn from bugs. Bugs which you meet as you are doing real world projects. So starting a project in python, and making sure you complete it, will really help you to become an advanced python developer. Also, patience helps. It takes some months to get there. Keep coding 😊.
as many as you need to understand the language basics i guess.
For example : I spend like a few hours with the Python Course and the language basics and then went from almost zero into my first "real" programm i finished yesterday. A calculator with useble GUI. I learned a lot more from that calculator than from the course here.