OP here. Your comments are helpful so far. To clarify some things: I know how a website works (HTML/CSS/JS, even with PHP & MYSQL or Node and a database) so I think my main confusion comes from frontend frameworks like React, Angular, Vue etc. Are they run on the server then the rendered version is sent to the client ? I've used browserify before and I thought it was "hacky", is this similar to how things are done usually ?
Thanks for your replies, I have seen great resources linked in the comments