Meditate: Literally train your mind to focus. It's going to the gym. Won't happen in a day, week, even month. Consistently do it and you'll eventually see progress.
Letting go: I have a long track record of starting while not going deep. Eventually, I just had to jump in the cold water and start letting things go. Literally put away physical gear for hobbies I wasn't actively engaging in but that took up a bunch of emotional and mental space and energy. Store it away and move on. Part of that process was telling myself this doesn't mean I failed or gave up or even that I would never do XYZ again. Just not now. I started learning the drums a bit ago then I also decided to try to get good at golf. Amongst other things, something had to go. Bye bye drums. Closed all the drums-related tabs. Put away the training material. It's golf time. Maybe in the cold months I'll pick back up, but for now, I'm relieving myself of the self-prescribed duty to practice drums. After doing that for a while, you feel a weight lift.
For some people, starting a bunch of things might be a way to protect against failure (or hard work) since they never actually commit to pushing something live. For others, like me, it's a lot of fun to learn something new (learn, not master).