This is useful - Lessons Learned
Definition:
A lesson learned is knowledge or understanding gained by experience. The experience may be positive, as in a successful test or mission, or negative, as in a mishap or failure...A lesson must be significant in that it has a real or assumed impact on operations; valid in that is factually and technically correct; and applicable in that it identifies a specific design, process, or decision that reduces or eliminates the potential for failures and mishaps, or reinforces a positive result.
Programs
https://www.buymeacoffee.com/pmpexamcoaching/extras
CAPM/PMP Study Group
https://projectcertifications.com/study-group/
YouTube
https://www.youtube.com/c/Projectcertifications
Agile Basics Course