I personally don’t like the idea of “studying” web development. I like the idea of learning through doing.
If you want to build a full stack app, then go out and try to build a full stack app. Get the tools you need to do it, and just start. Learn as you go, run into walls, and fail at every turn because you have no idea what your doing, but you will learn a lot because you have too.
If you want to fill your portfolio, then build something to put in your portfolio. Set some crazy short term goals for projects that should be possible (do it in 3 days), and grind to get to that goal. “Learning” or “studying” gets you and idea of what you can go out and really learn, but unless you use it you lose it right?
It sounds like you already know what things can do (JS, html, css, php, sql) but have you used them together ever? Maybe, maybe not, but probably not enough to be confident in them. As long as you have a rough idea of what tool is used where, you should have enough to go out and learn how to use those tools.
There’s a difference between knowing the path, and walking the path - Morpheus
I don’t believe in breakthroughs. There isn’t some “magical moment” you suddenly ascend to some level where you “do web development stuff”. I believe to get to where you want go you need to pick up your feet and take the steps. You might fall down, and run into issues after issues taking this route. You might get stuck for hours, or days, or even weeks (months?) on issues, but the only way that stops you is you give up.
The hardest steps are the first ones, since you know the least, so deciding that you are “going to build a form with realtime features in 3 months” might seem ridiculous, but again all you have to give (and lose) is time and effort right? Well thats all you need!
Good luck!
PS. I worked at McDonalds before. You might feel like you have more to offer, and that is very possible, but time is what it comes down to. McDonalds wants your time to work. You want to use that time to “learn”, I say spend that time “doing” as much as you can.