How can I become really good at understanding PCR and related lab techniques without direct lab access?

I have a background in microbiology and immunology, and I’ve studied PCR multiple times in the past. I’ve even done it once or twice, but I don’t have much hands-on experience. Now I want to become much more confident and almost “expert-level” in understanding PCR, gel electrophoresis, and similar molecular biology techniques, mainly from the theoretical and procedural side, since I don’t have ready access to a lab right now.

What resources (books, videos, online courses, papers, etc.) would you recommend for really mastering the concepts and workflows? Ideally, something that covers not just the steps, but also the common pitfalls, troubleshooting, and how to interpret results.