How to build a repertoire?

Databases are not the way to learn openings. They are a supplement of games once you know the openings you are playing.

You should NOT start out just by saying "I think I will play, uhm, The Nimzo-Indian Defense", just randomly picking and opening.

No, instead what you need is "Pawn Structure Chess" by Andrew Soltis. Go through the book in full, seriously studying it, not just breezing through it. It should take you about 20 to 30 minutes per page. This is like, a 100 hour project at least. If you study 10 hours a week, it should take you between 2 and 3 months to finish.

This will give you the foundation and from there, you can far more easily figure out which ones you best understand (NOT MEMORIZE), and play those openings. For example, if the pawn chains chapter makes a ton of sense, you may wind up a French player. Otherwise, maybe the 1...e5 structures, or Caro, or Sicilian makes more sense.

After you have completed the book, and you have a good idea which openings you should be playing given your own playing style, only then should you be studying openings, starting with the First Steps or Move by Move series and then following up with more dense and up to date references.

The above is absolute nonsense and will serve you very poorly as an 1100. What opening were you trying to learn?

Post 2 is not absolute nonsense. Stop giving out false information. Hate to break it to you, but that book along with a few other classics, like The Inner Game of Chess and a number of endgame books, got me from 1177 to 2000 in 3 1/2 years!

Try backing up what you say with facts before you start knocking what your superiors say!

Has it occurred to you that he probably doesn't want to devote time to a "100 hour project"? You don't actually care about assisting people, all your posts are concerned with lecturing your "inferiors".

"I did X and now I am rating Y, therefore it worked" is working from a sample size of 1. You haven't made master, so should I conclude that what you did is bad for anyone who wants to reach master? It seems to have seriously limited you.

Also don't you play 1. b4? Like you carefully studied pawn structures in a 100 hour project and then chose an opening that gives the same structure every time, OK.

WRONG AGAIN!

I am more than glad to assist people, but I assist with cold, hard facts. If you want to get better, you put in the time. I have assisted others before in person. I got one kid from 800 to 1200 in a year by going through fundamental concepts he needed to know rather than spewing opening theory. 800 or 1100 is NOT the time to be studying openings. You need to learn opening concepts (control the center), tactics, pawn structures, the concepts of doubled, hanging, and isolated pawns along with pawn chains, basic to intermediate endgames (ladder checkmate, lucena and philidor positions, OCB endings and how they are not automatically a draw, etc. You need the fundamentals (Pawn structures is one of them and the one that leads up to openings, hence why I specifically mentioned that topic and not calculation or endgames.

And your comment about 1.b4, yes I have played 1.b4. That is not all I have played. The 3 1/2 years I refer to are Early 1997 to late 2000. I never played 1.b4 until 2008. I played it 2008-2009, part of 2014, and mid-2022 until mid-2024.

I also played 1.e4, 1.d4, 1.c4, 1.Nf3, 1.g3, 1.b3, 1.Nc3, 1.f4, 1.c3, 1.g4, and 1.h3 at least once each OTB as White.

What did I play in 1997-2000? White - 1.d4/2.c4, 1.e4 (Ruy Lopez, mostly exchange, KIA, etc) and the Kings Indian Attack via 1.Nf3. Black - French, QGD Orthodox, and then experimented with the Leningrad Dutch and Pirc for brief times in 1999 and 1997, respectively, realizing then I was not ready to start experimenting and playing various offbeat openings, so I stuck to fundamentals until around 2002, then expanded. But the QG and Ruy are the best at teaching fundamentals. As far as the French and QGD, I was playing them before I even knew what an opening was. Obviously would be out of book quickly, but basic fundamentals formed my Black repertoire for me. It was what came naturally. I still play the French today, just not as my main defense to e4 any more, that is now 1...e5 and against 2.Nf3, the Petroff.

What I did initially is not why I am still an expert. It is what I did from 2002 onward. Purchasing opening book after opening book after opening book. I have played pretty much every opening except the White side of the London. Moral of the story is stick to at most 2 opening moves for White and 2 defenses against 1.e4 and 1.d4. Then focus on advanced fundamentals, which now I finally am and just in the last 2 months, my over the board rating has shot back up about 140 points. I have narrowed my opening repertoire, and while I still Crack open the opening books, it is under 25% of my study time, and I have condensed my repertoire to something an older person can handle. I pretty much play 1.d4 as White with the occasional 1.b4 (more likely for Blitz) and the Petroff, French (1.d4 e6 2.e4 or 1.e4 e5 2.Nf3 Nf6 3.Nxe5 d6 4.Nf3 Nxe4 5.d3 Nf6 6.d4 d5), and Classical and Stonewall Dutch.

Otherwise, it is game collections and advanced strategy books. I read Watson's Modern Chess Strategy, Franco's book on attacking chess, and now I am going throw Rowson's 7 early chess sins. I am also reading the 4 book bio on Korchnoi, which I am in book 2 right now.

And it is not a sample size of 1. Many others I know mastered chess through hard work and studying on a board. Even GMs, including the founder and owner of Quality Chess, whom has come to the club I go to probably a half dozen times!

I think, and this is an inflammatory comparison but I don't intend it as such, you are like one of those guys who is all "my Dad beat me as a kid and it made me the man I am today, so that's why we should all beat kids!". My peak is 2043 rapid and yours is 2125 rapid, so you are better than me. But are you really telling me that your learning methods are what accounts for your extra 80 rating points? If that is so, what accounts for the fact that you are not an IM?

For the record, the reason I was asking what opening OP was trying to learn is that if he's like "the Nimzo-Indian!" I will say OK, do not try to learn that at 1100, it's too complicated. "Go put in 100 hours of study in a pawn structures book" is useless advice for most people because they don't have 100 hours to devote to that. Moreover, it's just incorrect that this is the only way to improve. I have never read a pawn structures book in my life and I didn't have a real opening against 1. d4 2. Nf3 until I was like 1700, and my "real opening" against 1. d4 2. c4 was the Budapest. I have a ton more opening theory now, but honestly, even at my level it's probably added like 50 points to my rating, realistically. I'm hoping it will be a solid base to build from, but who knows.

just watch some YouTube videos on a couple beginner openings like the London or carokann or something and then practice against bots I guess

I already answered that question in post 6. I am not an IM because I got all hung up in Openings from 2002 until last year. It all circles back to the initial point. Don't get all gung-ho about Openings. Do what is critical and let the openings come to you. I stopped that approach in 2002 and shouldn't have! That's the whole point. Then getting married in 2006, having a kid in 2010, aging, and work are all getting in the way of improvement. At my age, I will never be an IM. At this point, the goal is NM.

Also, I guarantee you he has 100 hours. I never said 100 straight. That would likely be spread across 10 to 20 weeks (5 to 10 hours per week). Is he spending an hour a day playing on here? Is he spending 30 minutes a day putting up posts on the boards? He could spend that hour and a half each day (10.5 in a week) studying Pawn Structures.

And also, I don't play a lot here. I play far more over the board, like the following rated game I played last Tuesday night (I will have another tonight against a different opponent, likely as Black):

Was the play perfect? Absolutely not. But studying and playing over the board is far more useful than 3 minutes blitz here and looking at a bunch of unannotated games from a database.