The original YSAP: The answer is YES with a BUT depending on your goals. YES this book is designed to help a piano beginner pick up some skills. BUT learning strictly from a book can be difficult. If you’d like to advance your piano playing, my best advice is to find an experienced teacher to supplement the book. Or at least someone you know who knows more than you that you can bounce questions off of!
YSAP 2 is an intermediate level follow-up book to the original. 20 Piano Pieces for People with Emotional Problems range in difficulty - some easy, some intermediate, and one really, really, really hard one.