Ground Schools:
FLY8MA: https://learn.fly8ma.com/?ref=68
Ground School Academy (M0A) https://ud165.isrefer.com/go/ogsa/squidman84/
King Schools: kingschools.com
Learn The Finer Points (Jason Miller) Look up on YouTube.
Text Books
The Airplane Flying Handbook https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/airplane_handbook/media/airplane_flying_handbook.pdf
The Pilot’s Handbook of Aeronautical Knowledge https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/media/pilot_handbook.pdf