I've used https://www.freecodecamp.org https://www.freecodecamp.org to refresh on a few subjects and pick up some new tech that I needed. They also have coding

I've used https://www.freecodecamp.org https://www.freecodecamp.org to refresh on a few subjects and pick up some new tech that I needed. They also have coding challenges and interview prep. You might also want to start hanging out at meetups - many are virtual now. When user groups open in-person again, they're a great way to meet other devs and pick up work.