How to improve blitz chess rating?(Time management) I have a blitz rating of 1900 on Lichess and I can't seem to improve from there. My road to 1900 was fairly quick, but I have been stuck in 1900. My Classical rating is higher than this, so I know that it is a problem with shorter time controls. I have noticed that I spend too much time throughout the game and that is the reason. Can someone please explain how do I manage my time well throughout the game.
Blitz is a bit of a different chess "animal". In order to play blitz well, you need a few things, and that is great tactical vision, good time management, and some positional skill so you can make decent moves quickly in quieter positions. It also helps to be young because you think faster when you are young.

The first part to getting better is obvious, and that is work diligently on your tactics. Do a lot of them in a short period of time for the best results. I also recommend reading games, especially fun tactical ones, without a board. This will also help your vision.

As far as time goes, personally, I hate falling behind on the clock at any time control, but it is more crucial in blitz. If you do fall behind, it cannot be by too much...ever. You simply have to play fast, and keep an eye on the clocks at all times to stay ahead on time, or at least, close. Only every now an then, can you afford a longer think.

The positional skill comes with time, and reading a lot of books about pawn structures, and other positional elements will help with this. I strongly recommend the Yusupov series of books as they cover all areas of the game. This may not be good for your regular play and long-term chess development, but also if you play openings that have very standard places for the pieces, like the Stonewall, or London System, you can save time in the opening.

Lastly, you just need to play a lot, although this may not be conducive to your classical rating as you can become shallow. Personally, while it is fun, for a serious player, blitz is not the best think for your game (Botvinnik agreed), but it can be especially useful for testing out your openings.

P.S. I know that 3-0 is a common control, but you can also play 3-2, or 5-3, which is still fast, but gives you a little more time to think. Conversely, you could also play some bullet, and when you go back to regular blitz, it will feel like you have a lot of time.

There is actually a whole book on the subject here. For the record, although I have a lot of books, I do not have this one, so it may, or may not, be any good.

Again, be aware that this may not be good for your tournament chess, if you play tournaments.