How to gain a working knowledge of video

I really enjoy using analog video gear. As an audio person, video feels like a whole new world! However I find I’m running into walls that reveal my gaps in knowledge, and I’m seeking a deeper understanding. I wanted to ask here for advice and resources to gain a more practical working knowledge of how video works, so I can do more with what I have. I wouldn’t say I’m a beginner but i am needing some basic knowledge.

For instance here are some questions I feel I’m swimming around in the dark with; - how to transfer video to/from different resolutions without it getting messed up— A laptop to a vhs, a vhs to a laptop (I have been using vidbox but wish it could look better). - how do time base correctors work and why do we need them? - why do I need a powered piece of hardware to convert hdmi to rca?