How to get better at chess

I have maxed out my ratings around 1600-1700 for blitz and rapid.

How do I improve without any coaching or courses?

https://lichess.org/forum/general-chess-discussion/how-to-improve-my-lichess-rating#2

https://lichess.org/forum/general-chess-discussion/im-cant-get-2000-blitz-rating?page=1

Maybe try one of these:
Best Lessons of a Chess Coach
https://www.amazon.com/Lessons-Chess-Coach-Sunil-Weeramantry/dp/1936277905/ref=sr_1_1?hvadid=241641906121&hvdev=c&hvlocphy=9033692&hvnetw=g&hvqmt=e&hvrand=2647734780913502312&hvtargid=kwd-362968625&hydadcr=15969_10361249&keywords=best+lessons+of+a+chess+coach&qid=1684474574&sr=8-1
"... [Simple Chess by GM Stean] will definitely help players in the general rating range of 1300-2000 with their positional play and strategic thinking. ..."
https://web.archive.org/web/20140708104258/https://www.chesscafe.com/text/review400.pdf
https://store.doverpublications.com/0486424200.html
"How to Reassess Your Chess, 4th Edition was designed for players in the 1400 to 2100 range." - IM Jeremy Silman (2010)
https://web.archive.org/web/20140708095832/https://www.chesscafe.com/text/review769.pdf
https://www.silmanjamespress.com/shop/chess/how-to-reassess-your-chess-4th-edition/

@kindaspongey said in #3:

Maybe try one of these:
Best Lessons of a Chess Coach
www.amazon.com/Lessons-Chess-Coach-Sunil-Weeramantry/dp/1936277905/ref=sr_1_1?hvadid=241641906121&hvdev=c&hvlocphy=9033692&hvnetw=g&hvqmt=e&hvrand=2647734780913502312&hvtargid=kwd-362968625&hydadcr=15969_10361249&keywords=best+lessons+of+a+chess+coach&qid=1684474574&sr=8-1
"... [Simple Chess by GM Stean] will definitely help players in the general rating range of 1300-2000 with their positional play and strategic thinking. ..."
web.archive.org/web/20140708104258/https://www.chesscafe.com/text/review400.pdf
store.doverpublications.com/0486424200.html
"How to Reassess Your Chess, 4th Edition was designed for players in the 1400 to 2100 range." - IM Jeremy Silman (2010)
web.archive.org/web/20140708095832/https://www.chesscafe.com/text/review769.pdf
www.silmanjamespress.com/shop/chess/how-to-reassess-your-chess-4th-edition/

Thinking of reading 'Simple Chess' as well, sounds like it's good stuff!

It did not seem simple to me when I read the first two chapters, but it seemed like the sot of material that would have been helpful if I had kept at it.

If u have already mastered basic of opening and middle game, then u should focus on endgame...the hardest

"... Silman’s Complete Endgame Course ... Silman ... time and again has shown the ability to reach those who feel intimidated by the lofty approach that a grandmaster will often take.
... he defines what he thinks is necessary to know at specific rating levels. For example, the beginner or unrated player needs to know how to checkmate with an extra queen and rook, two rooks, and finally with a lone extra rook. Second, he or she must understand the difference between checkmate and stalemate. But no more! Silman's idea is to wait until you climb in strength before you worry about more advanced material. Then, as a Class 'E' player (that's 1000-1199), one must learn with what material you can mate, and learn queen versus bishop and queen versus knight. Mates with two bishops and bishop and knight are left for later. But you are also introduced to the concept of 'opposition' and playing the most elementary king and pawn versus king ending. ... In Class D (1200-1399), one begins to use the 'opposition' to win (or draw) king and pawn endings when the king is in front of it's own pawn, and here for the first time we add more pawns and see the idea of one pawn holding up two, followed by how to win by allowing your passed pawn to be captured while winning the opponent's other pawns. The D player also learns about distant opposition, and cases of a single piece versus a lone pawn. And so forth all the way up to master.
... Silman's book emphasizes to the student that the important thing is to master the strictly limited material at hand, rather than get confused by endings that won't help your results at that level. ..." - IM John Watson (2007)
https://theweekinchess.com/john-watson-reviews/theres-an-end-to-it-all
Silman suggested that players in the 1400-1599 range read up to page 158 in his book. I imagine that he was thinking in terms of USCF ratings when he wrote that.

@KDMFan said in #1:

I have maxed out my ratings around 1600-1700 for blitz and rapid.

How do I improve without any coaching or courses?

Learn to live with repeaters.

@kindaspongey said in #7:

"... Silman’s Complete Endgame Course ... Silman ... time and again has shown the ability to reach those who feel intimidated by the lofty approach that a grandmaster will often take.
... he defines what he thinks is necessary to know at specific rating levels. For example, the beginner or unrated player needs to know how to checkmate with an extra queen and rook, two rooks, and finally with a lone extra rook. Second, he or she must understand the difference between checkmate and stalemate. But no more! Silman's idea is to wait until you climb in strength before you worry about more advanced material. Then, as a Class 'E' player (that's 1000-1199), one must learn with what material you can mate, and learn queen versus bishop and queen versus knight. Mates with two bishops and bishop and knight are left for later. But you are also introduced to the concept of 'opposition' and playing the most elementary king and pawn versus king ending. ... In Class D (1200-1399), one begins to use the 'opposition' to win (or draw) king and pawn endings when the king is in front of it's own pawn, and here for the first time we add more pawns and see the idea of one pawn holding up two, followed by how to win by allowing your passed pawn to be captured while winning the opponent's other pawns. The D player also learns about distant opposition, and cases of a single piece versus a lone pawn. And so forth all the way up to master.
... Silman's book emphasizes to the student that the important thing is to master the strictly limited material at hand, rather than get confused by endings that won't help your results at that level. ..." - IM John Watson (2007)
theweekinchess.com/john-watson-reviews/theres-an-end-to-it-all
Silman suggested that players in the 1400-1599 range read up to page 158 in his book. I imagine that he was thinking in terms of USCF ratings when he wrote that.

While its not as useless as amateurs mind, i wonder how can it be a complete endgame course?

I mean if you finished the book, can you come up with endgame plans in the middle game? If not, how can your endgame course be completed?

Perhaps Silman had it in mind that the book would be complete with regard to the needs of a player up to some level or other. I don't think that Silman was trying to fool people into thinking that all endgame knowledge was included in one book. For one thing, he made suggestions as to where to go to learn more. However much one may complain about the word "complete" in the title, it is just one word. As far as I can tell, the contents of the book present a respected introduction to endgames, with some sort of approximate indication of how much one might want to know at various rating levels.
As for Amateur's Mind, as I have written before, it does not seem likely that it was intended to be very useful to you.