[Too]

The problems you describe have very little to do with docker itself, they sound more like integration challenges.

For example. Docker has absolutely zero knowledge of the branches lifetime or even branches at all. This is something you have to design using the existing capabilities of docker together with features or existing integrations provided by GitHub or bitbucket.

Of course knowing docker deeper will help you understand these boundaries better and use them.

One secret is that there is actually not much to it, most things are just variations of docker run and various tricks within docker build, sprinkled with some volume and image management like tagging and pruning. Other orchestrators like GH Actions, Compose, Kubernetes etc can be seen as building around these basic blocks.

If you already know these basics, you are probably going to learn faster by getting your hands dirty, trying to solve the scenarios you need, rather than binge watching tutorial#187 on YouTube.