I can't teach you how to code (loaded question right there) but I can give you some resources that might help. I myself learned through observing other people's codes (there is a TH account dedicated to archiving them here) and just messing around hoping things go right, but I'm not sure I can really recommend that. You can use this website to see all your changes live.

As for the resources, here is a list of common properties and basics relevant to TH coding (it's towards the end of the page). You can also join the TH coding discord server here, you can ask for help as well as show off what you've done (and also just talk rlly)!