Using PGNs to Study?

I have 5 PGN courses. They are good courses. I know how to load them into chessbase or any phone reader, that's easy. They each have dozens of chapters. How the heck do I effectively study with these. I know it's me but I can't believe there isn't a video showing how to take these lessons bit by bit and implement them. If you know of a PGN study guide video please post it I can't find anything besides how to load them (which is not hard) but nothing about how to educate yourself with them. Any advice would be great thanks

have you found the solution yet?

LOL....it took 4 years but yes I did....Chessly.

It actually kind of worked out bc these were Gotham courses and anyone that had even one course he gave an insane locked in subscription fee for his entire website. Now I have every opening course you could ever want for several lifetimes.....