By all means have a look at CAP493 (MATS Part 1), but I would caution you about trying to 'learn it'. Without the help of practical experience (either already gained, or at the college in the sim and classroom) it would probably confuse and make things worse!
If you'd like to get a head start, consider the Trevor Thom PPL guides, or the AFE PPL guides. Basic Met, principles of flight, Nav all help in your training.