2000 plateau

Well, technically 1950 plateau, but my highest is 2020, but the thing is I've been stuck here since November, my previous plateaus went off quick enough, but this one isn't going away!

Play and analyse, tactics from Ivaschenkos school of chess studies book 2 (from level 6), and occasionally I study openings and endgames, but the latter I study the least.

It's very easy to know what to recommend just by seeing that you're a rapid game player.
If you train as you currently do but add at least three days a week practicing specific mating exercises (that don't involve patterns and require you to calculate every move), this will help you play more accurately in the critical positions of your games. Download 700 Chess Problems by W. J. Baird; it's completely legal to download it for free. Start by solving checkmate exercises in two moves. When you can solve at least 10 consecutive problems without feeling any mental fatigue, you can move on to practicing checkmates in three. It's preferable if you can solve at least 20 mate problems in two consecutive moves without feeling any fatigue.

I recommend that you take your first few days of calculus training very seriously. Do it at a time when you're not tired, and make sure you drink enough water so you don't feel thirsty. Use 45 minutes or 80 minutes as your estimated training time; it's a matter of preference. It doesn't matter if it takes you 80 minutes trying to solve a single problem; over time, you'll discover the correct way to calculate each move in less than 2 minutes with the two-step checkmate exercises and less than 5 minutes with the three-step checkmate exercises. Getting good at these exercises will take weeks or months if you're disciplined. Never look at the solution at all; always try to solve it with your own effort. Only if you spent at least 45 minutes on the first exercise can you see the solution, but from the second exercise onward, never look at the solution. It's the same with three-step checkmates; on your first attempt, don't look at the solution until you've spent at least 60 minutes calculating. With the second problem onward, never look at the solution and try to solve it yourself. With the first exercise, I'm referring to the entire collection, not just the training day. Seeing the solution to a single problem will give you an idea of ​​how detailed the solutions are.

A training time of 45 or 80 minutes is the maximum time you should set. Once you calculate faster and can easily solve a maximum of 20 checkmate problems in two, that will be enough. Once you can solve 5 or 10 checkmate problems in three, that will be enough.
If you can't solve a single exercise, you'll learn its flaws and correct the mental processes that cause you to get stuck in your calculations. The goal is to learn to calculate as best you can; speed will come naturally over time. To strengthen your memory, try memorizing chess games consecutively, just the moves without the analysis. Improving your short-term memory will make it much easier to solve checkmate problems, especially those with two moves. Short-term memory is very important because you'll need to calculate the same moves less and less repeatedly, and it will prevent you from forgetting moves you've already calculated minutes or seconds ago.

This training is good to repeat if you decide to give up. Over time, your improved calculations will lose quality, but some of this training will have very long-term benefits that will likely last for years. Obviously, it's not realistic to calculate every move in a real game, but in these problems, you must calculate every move until you find the correct solution.

This training is good to repeat even if you give up. Over time, your improved calculations will lose quality, but part of this training will have very long-term benefits that will likely last for years. Obviously, it's not realistic to calculate every move in a real game, but in these problems, you must calculate each move until you find the correct solution. Training your calculations will improve your rating. Since these are rapid games, I recommend losing your fear of running out of time. Even if you manage your time poorly, your brain will adapt, your calculation speed will improve without you realizing it, and you'll learn to take advantage of winning advantages to finish games with little time on the clock.