Where can I find good methodology to get better?

Hello!

I believe that all you know and what was said in the previous posts  are also valid and 
I suggest  that  you also  play  with bots of Chess.com.
It helps a lot...

Greetings from Curitiba

Hanging Pawns has a good video series on Youtube about the Italian he does a few series on openings I would recommend it.

#15
"Do you think 4 puzzles is really enough?"
++ Yes. Puzzles are helpful as a warm-up, but in a real game nobody tells you if there is a tactic and for which side. Practicing penalty kicks is useful for a soccer player, but a whole practice session of penalty kicks only does not help.

"It takes me in avarage 2.5 minutos to solve a puzzle in my current level."
++ As in a real game you do not know if there is a tactic or for which side, you should spend 5 minutes per move in a real game. You should play 15|10 at a pace of 40 seconds/move.
That means you should solve tactics puzzles at a pace of 20 seconds per tactics puzzle.

"I started a few days ago to analyze all my games, even the ones I win"
++ I recommend to analyse lost games only. You learn more from a game you lose than from a game you win. It will also stick better in your memory. This also counteracts the natural but bad habit to spend much time on pleasant won games and to dispose quickly of unpleasant losses with some lame excuse: 'stupid blunder', 'short of time', 'silly opening'.
Analysing your own lost games is key to improving,
otherwise you make the same errors over and again.
Study of an annotated grandmaster game helps more than analysis of a game you won.

"I will try changing from blitz to rapid."
++ As you spend 2.5 minutes on a tactics puzzle even 15|10 may be too fast for you.

I see that people recommend  studying openings, endings, tatics, reading books, etc, and I also know that everyone can get better by its own way, some would prefer to spend more time studying openings while others analyzing games but is there a general methodology to help begginners improve? Such as studying X hours of openings, making Y tatics puzzles per day, etc?

Chess, like any other skill, has a "core skill" that you absolutely must be good at in order to improve. For example in football the core skill is to be able to control the ball very well with the feet while moving around and unless you do that everything else is essentially useless.

In chess that "core skill" is your ability to visualize or lookahead a certain number of moves. So the better you are able to visualize the board in your head after X number of moves, the better u get at chess.

So my advice is to not bother at all with openings, theory or strategy. Just spend time trying to improve your look ahead, things like "if he moves the pawn here, i move my knight here, he takes, I take and he moves his queen here then what would the board look like"

#24
"If you do faster than that you get Full points in the puzzles"
++ Do not worry about puzzle points.

"do you think I should try solving them faster ,lets say using only 30 seconds"
++ No, the other way around: you should play a time control that allows you to think longer than the time you use to solve a puzzle. 15|10 is 40 seconds/move, 25|10 is 60 seconds/move, 45|45 is 135 seconds/move. It is pointless to guess the solution of a puzzle. If you need more time to solve it, then take that time. However if you need so much time to solve a puzzle, then you also should play a slower time control that allows you more that that time to find your move to play.

Improving Your Chess - Resources for Beginners and Beyond...

https://www.chess.com/blog/RussBell/improving-your-chess-resources-for-beginners-and-beyond

There is an article on The Italian game in my Chess.com blog...

https://www.chess.com/blog/RussBell