The best tutorials I’ve found on YouTube were from Animation Mentor.
Not only do they deconstruct character movement, but have general animating tips as well. The classes uploaded by the mentors are easy to follow and insightful!
A few examples of what I looked at for the walk cycle/ body mechanics:
Playlist available at: https://www.youtube.com/playlist?list=PL_KRGEJDeziUGg6t_VY4uYCw9Vr4OhZP6