Fast thinking.

In blitz, oftenly lose by time in winning positions, but if I play fast, I generally get losing positions. What should I do? Do you have any tips for me to think faster?

All the time play de same, learnd one opening with White and one opening black, and and only play theses

I mean, I play fast in the opening phase. Is in the middlegame where I'm slow.

Slow down to go fast. Play longer time controls to develop the right technique first. Your faster games will then improve. Develop correct and good technique first, then speed it up. It's the true for most skills.

Ok.

WDYM?

Are you aggressive in your opening game? I play daily, up to 5 days a move, so I'm guessing that blitz would be attack & attack, push for opponent mistakes, I've tried it's not easy, I would like to do blitz myself, but I shy away from full on attack early. You say you play fast in opening, but is it aggressive as well?

Not really. I'm very bad at playing aggresively.

it is a bannable offence to post links, so i would suggest that you either delete your post, or edit it

@IAmPomi, they are right. If you are having trouble playing blitz, switch to rapid games, like 30m,15+10, or 10m although I would suggest the first two for you if you are having trouble with time. The faster the time control gets, the less the game is about skill and precise calculation, it instead becomes instinctual. Give yourself time to develop in slower chess and attacking will come naturally. You will begin to get a feel for what moves are good, and what moves are not, even if it isn't a blatant blunder. I would also suggest that you do puzzles. Lots and lots of puzzles. Being able to see tactics quickly will help you in the middlegame. If you are looking for long-term improvement, would suggest that you get a chess coach. It isn't easy to learn something completely new without the help of a seasoned player, whether it be a 1500 player or a 2500 player. Either will work. They will work through complicated endgames with you and analyze master games with you. Which brings me to my next topic, master games. Analyze them. Those people are called masters for a reason. Find analysis with text explaining each move, whether bad or good. It will help you understand the opening, the middlegame, the endgame, attacking, defending, tactics of all sorts, and on and on. So, uh yea that's your advice from a 15-year-old. Hope this helps!

Thanks! Also, how many puzzles a day do you recommend me?

I made a similar mistake when I started to play, I purely played blitz and bullet so I fail to succeed in rapid/daily games since I just want to go fast. Don't do that, play like 15 10 or 10 15 games. 

Honestly, the thing that helped me most when I first started was the chess.com lessons feature. The ability to solve puzzles comes a lot easier after you finish all of the lessons excluding the mastery ones (there are about 4000, if you have the time, I recommend it, otherwise, don't bother and only do the attacking/endgame ones). Even if things such as basic opening principles and 1000 level tactics seem repetitive and pointless, still do them, it is one of the best ways to get it cemented into your mind, you can't play fast without a little bit of instinct.  

Why do you want to play fast? Play slower over longer time controls to improve. 

First if you keep on losing on time, then change your time control, you should always play a time control that fits you. If you want to improve thinking speed, play bullet, but dont go for random moves try as much as can to think basic, this is a process that takes time, doing 3min puzzle rush should help, and just improving your clicking speed (you can use chess.coms vision to help with this in the learning section) and thats all from me!

I want to score 100000 in my bullet rating

@IAmPomi, Do 30-40 puzzles a day if you have a membership that allows it, otherwise just do as many as you can

easier said than done, but 100000, not even possible, 2000 maybe one day, good luck.

This is kind off topic, but it still applies to chess. In game shows people often give into their emotions and feelings rather than thinking logically which makes them lose on the big prizes. Its not really about thinking faster, but to stop panicking when you are low on time. Keep on thinking logically and you'll eventually win.