The best way by improving in chess is not necessarily by playing...it is actually by studying. Grandmasters spend countless hours doing chess puzzles. And by doing chess puzzles, you learn mating sequences.
What is best way to improve in chess?

Hi! My name is Lauren Goodkind and I’m a respected chess coach and chess YouTuber based in California:
https://www.youtube.com/channel/UCP5SPSG_sWSYPjqJYMNwL_Q
I have tips and resources to help you improve your chess skills so you can win more games.
-I offer a free beginner’s free eBook on my website, in case you are interested. The book is about asking questions before each move.
-Learn basic tactics such as the fork, discovered attack, pin, and more. I offer interactive puzzles on my website:
-I recommend two books for you: “50 Poison Pieces” and “Queen For A Day: The Girl’s Guide To Chess Mastery.” Both books are available on Amazon.com. Both books are endorsed by chess masters!
-If you are serious about chess, I highly recommend you hiring a chess coach to help you.
-Also consider all checks and captures on your side and also your opponent’s side. Always as, “If I move here, where is my opponent going to move?”
-Play with a slow time control, such as G/30 so you have plenty of time to think before every move.
I hope that this helps.

I will repeat what I have started to use recently because much of the 'advice' that I have seen here has done nothing to help my chess.
There are tons of free resources without wasting your time and money on expensive training, books and software. Check out the lessons here on chess.com. There is also an extensive collection of excellent videos on chess.com. Puzzle rush and practice drills are also available and will help.
Second excellent resource would be youtube. There are excellent trainers and GM's on youtube giving out free advice. As a beginner I would recommend the chessbrahs 'chess habits' series. https://www.youtube.com/playlist?list=PLUjxDD7HNNThftJtE0OIRFRMMFf6AV_69
Chessable is another great resource. There is pay content, but I there is also tons of free courses. https://www.chessable.com/
Finally, I would recommend a simple free program to 'guess the move'. This program goes through games and allow you to guess the move and checks it against an engines choice. I prefer this program to most books because many books (and almost all older ones) have faulty analysis and have errors that have been exposed by todays engines.
https://sites.google.com/view/fredm/home
a great collection of pgn files to use with Guess the move can be found here. http://www.pgnmentor.com/files.html

Play longer games where you have to time to think and consider your moves. No blitz, definitely no bullet. 30 minutes or at leas 15. Think before moving. Look for checks, captures, hanging pieces.
Every GM started as a beginner, and they studied a lot, but most importantly they had fun while doing so.... try setting small milestones like 300 rating, then 400, then 500 . One step at a time. Here is a quick guide to increase your rating.
Learn these basic endgame checkmating patterns
-King, Queen & Rook vs King
-King & Queen vs King
-King & 2 rooks vs King
-King & Rook vs King
(Some middle-game checkmating patterns will help as well but I don't know what they're called and I don't want to make you learn more than that and some of them can be learned by doing some TACTICS PUZZLES)
If you don't checkmate your opponent in the middle-game (or opening - hello scholar's mate) and your opponent does not resign you're very likely to get one of those, so it is very important that you know how to convert those. Because they are won positions and you need to know what you're doing, otherwise there is no point because you're not going to win
Once you got those checkmating patterns down we move on to the next stage
Learn opening principles (not memorizing moves, but learning and understanding opening principles: developing your pieces, controlling the center, castling your king to safety, connecting rooks). These will help you get a better middle-game where you have a better position with more chances of winning.
In the middle-game make sure you don't hang any pieces, your opponents eventually will hang a piece. When they do, capture that piece.
Now that you're up in material, trade down (think of a soccer game.. if you're playing 11x10 that's a good advantage, but if you're playing 2x1.... you're still up by one, but it's much easier to win and a greater advantage, the same applies to chess).
Once you traded down into a favorable endgame, apply one of those checkmating patterns I mentioned in the beginning.
Chess.com has plenty of resources that help you... check them out
Also look at some GMs game to understand how they think and what their plan/strategy is...
Maybe agadmator... I recommend John Bartholomew he has some good content, I heard chessbrah has a series where they explain the mistakes of each rating as well.
If you're really decided to be a GM at some point you're gonna need coaching, why not now.... Lauren seems like a great teacher and it'll definitely speed up the process of increasing that rating
Good luck

Improving Your Chess - Resources for Beginners and Beyond...
https://www.chess.com/blog/RussBell/improving-your-chess-resources-for-beginners-and-beyond
Most important is to check your intended move is no blunder before you play it. This little mental discipline alone will bring you to 1500. As long as you hang pieces and pawns all the rest is in vain.
Solve 4 tactics puzzles each day as a warm-up.
Play 15|10 games and whenever you lose one, stop playing and analyse it to learn from your mistake.
Study annotated grandmaster games.

Thank you everyone for your replies! I want to tell one thing that I am not that serious about chess I play it cuz I enjoy it. I did say that I wanna get to the GM level but I did not know I had to play professionally. So, the important points that I got form here are:
1) Puzzles are really important.
2) Analyzing the game also helps in improving.
3) I should play longer games so that I get more time to think.

Mostly because I know only one way to checkmate that is the 'Scholars' Mate'. Kindly tell me more methods/ways to checkmate.
All the advice in this thread sound reasonable. However, based on the quote above, I'd say that the opening poster needs much-much-much more basic advice.

Mostly because I know only one way to checkmate that is the 'Scholars' Mate'. Kindly tell me more methods/ways to checkmate.
All the advice in this thread sound reasonable. However, based on the quote above, I'd say that the opening poster needs much-much-much more basic advice.
I can't take lessons I am not a premium member
Hey there,
I am a beginner in chess I really want to improve a lot. I literally wanna reach the GM level. My rapid rating is 140 or 150 I guess. But I have defeated level 1- level 9 engine. A lot of people say that you can improve by playing more games but every game I play it ends up looking the same. Mostly because I know only one way to checkmate that is the 'Scholars' Mate'. Kindly tell me more methods/ways to checkmate.