You probably retained more than you realize, but I can tell you that I've been coding for about 25 years now and I constantly refer to documentation for the too

You probably retained more than you realize, but I can tell you that I've been coding for about 25 years now and I constantly refer to documentation for the tools I use. "I don’t feel sharp" Don't equate not knowing how to do something with being inept. Making something from scratch that's not been made before is often an adventure into the unknown that requires a lot of trial and error. It's often our job to figure out how to do it. For me, that's the fun part, but the journey to get there can sure make you feel dumb as a bag of hammers. That's because there are almost always a lot of ways to do it both wrong or better. But the truth is you just need to find one way that does it. "Improvements" are future tense. So you focus on the problem in hand and move along a step at a time. I've learned to seek help as soon as I get stuck, as opposed to a hardheaded "keep tossing mud to see what sticks" approach. A few days of that can make you feel stupid real good. It was ego that prevented me from learning that lesson sooner. Ego can take a pounding when you're hard headed. So toss ego aside and start looking for and asking for help as soon as you hit a wall. My experience since is there are very few problems without solutions, or at least partial solutions you can build upon. You probably do know where to start looking for answers to questions and help for most of the issues you'll ever run into, and that's what will keep the progress going on whatever you're working on. If you think about it, finding the answers is what you really learned how to do in school, and you still know how to do that, and you always will. I'll also offer that you work on something for you. Grab a raspberry pi and one of the projects for it that looks fun and diddle with it. It's exercising. It keeps you sharp and builds confidence. Make something and share it. That said, I've got some Pi projects I did a few years ago that I glance at now and wonder how the hell it works because I forgot, but if I dive back into them it comes back to me. So just dive in. You'll be welcomed.