Whichever method you use just to pass the exams, I would suggest that you should buy & retain the full set of one of the well known series of ground school manuals.
I found that after I had got my PPL, I still went back to the books to check various bits that I had forgotten, or that I thought I needed to understand more thoroughly.
Even now, many years after getting my licence, I still go back to the books, often after reading something on Pprune, which makes me realise that I have forgotten/misunderstood something!
I never finish learning about flying.
I am still trying to improve.
