Yesterday you asked about books on "python, django, and web dev". That's a good start. Many languages can be used for web apps, it's more important to start and pull through with the learning resources.

Given what you're going for, Javascript will be your most important friend, followed by css even if you aren't a designer, as well as html. It's worth also learning git. Still, you'll have to learn more the concepts, and even then you have to roll with the punches. We're all re-learning constantly.

Good luck!

Css/javascript/html

Node for the backend will also use javascript.

That could take you a very long way if you want to just hack out a product.

If you go the javascript route, I like koa/node/mongo and vue.