I think there are some basics, that every developer should know to understand how the web works and to get to know the possibilities you have. I would say that these are basic html, css, js and php. After that, you have to decide on what you want to focus, front-end or back-end development.
But in my opinion its best to not become an expert in only one language, but to raise your skill level in multiple languages at the same time and learn how to combine them etc. So for example, html and css go hand in hand and you will get better in html while you learn css and vise versa. Now, if you feel comfortable with those two, start learning js / jquery and try to combine everything you know, like using js to animate your site etc etc..
After that, look out for frameworks like angularjs, vuejs, laravel etc, which will improve the way you use the basics.
Basically I would say - learn the basics until you can think of solutions for most ideas that you have, wether or not you know exactly how to code the solution. I think every developer on this planet has to look up something here and there, nobody knows everything, thats just impossible. But its possible to know what you have to look for.
I also think, that it is a great advantage, if you find a good workflow for yourself early on. So decide which editor you want to use, get to know git, node, gulp and so on and don't just google for "how to setup your pc for development" but try out different things until you find something that fits you the best.
I am on windows and worked with xampp for many years for example and just recently found "laragon" when I startet to learn laravel. Laragon is so much easier for me to work with than xampp so I dismissed xampp completely.. I don't know how long it is around, but if I would have looked for alternatives instead of just going with the first google result I think I could have been a bit more effective than I was with xampp.
Finally, I want to share a very nice video from Learncode.academy in which they explain what options there are and for what kind of work you should get to know them etc:
And this is the mindmap used in that video: https://coggle.it/diagram/Vz9LvW8byvN0I38x