As others have implied, I'd lighten up on the sim and hit the books, the attached link is an FAA publication called Pilots Handbook of Aeronautical Knowledge that is downloadable, free and covers pretty much everything a young person starting out on a PPL needs for reference material, as you're learning in the UK/EU I'd probably skip the first chapter on the FAA's history.
https://www.faa.gov/regulations_poli...t_handbook.pdf