Thonny is a Python IDE right?
I may be missing something here, but… are you trying to debug C or Python?
AFAIK Micropython does not offer a debugger (yet?)
My recommendation is to use lv_micropython.
I don’t see much benefit in an effort to port lv_binding_micropython unless you have to (for example, to support CircuitPython or some other Micropython fork).
If you still want to use lv_binding_micropython directly, I recommend using git to find the differences between lv_micropython and upstream Micropython (v1.18) so you could see all the changes that need to be done in Micropython to support LVGL.