desenvolvimento web

Dears, good morning

I've been developing cache scripts for over 25 years, my entire ERP system has cached scripts, everything is global, no graphic/web screen.
I have a little knowledge in JS, Html and CSS, and I'm wanting to start web development for my system, go gradually.
I would like if you can help me which would be the best option in development to be able to start. As I live in a region with few training options and specific courses, I will have to take a distance course.
If possible, and if someone can, of course, send me a model accessing the cache base, so that I can have an idea of how to start, I would be very grateful.

Anyway, thanks for everyone's attention.

Att
Davidson Espindola