Learning an Opening Repertoire.

@BeerisFree learning 30+ lines won't help at a low level anyway because most likely your opponent doesn't know theory, which means that after move 4, you will be out of book anyway and will need to play chess.

Thanks... I guess...
Well then, could you suggest me what parts of the game I should practice/study more? I will upload two of my last games (on another account), one lost and one won. On the lost one I know I've done 2 very dumb mistakes (losing a rook and not noticing two-rook-checkmate), but what do you think I should improve? Opening, mid game or anything else? Thank you a lot.

WON GAME (playing Black):


LOST GAME (playing White d4):

Please request a computer analysis for both games to see the answer.

A computer analysis won't help me know what part I should improve (op, mid or end)...
I've analysed the game already (first by myself, then with the computer), and I understand the mistakes I've done.

Thanks for the reply, hangrad^^

By quickly looking into the games, I can see that some moves were not useful. It's important to develop and control the center. In second game, I don't like 4. h3 and 5. a3 for example. It's better to develop knights and bishops to better squares. You should focus in finding the best way to organize your pieces so that they do not interfere with each other. You need to train both tactics and strategies because tactics arise out of superior positions.
The key is every time it's your move, you play the best move you can see.

@BeerisFree, I've analyzed the second game of yours in depth and put it in a study:



Overall, from that game, you really need to work on developing your pieces out of the gate; you also need to work on your sense of danger by asking yourself after every move: What is my opponent threatening by moving that piece there? How can I counter his plan? You always want to be thinking about how to defend against your opponent's plans, and you'll find that in asking these types of questions, you will start to intuit good candidate moves. There are some other positional considerations that you can start thinking about (I made note of some in the study notes), but these two are the most pressing, I think.

Let me know if you have any questions. Cheers! DLT

The game you won is of little interest, as your opponent played weakly. 4 h3? Nxe4 is won for black. You played that one well.

The game you lost is more instructive. Agree with #15: moves 4 h3? and 5 a3? are weak: these weaken your position and do not contribute to either the development of your pieces or to the control of the center. Black plays himself 5...h6? and 7...a6? as well, so that nullifies your weak moves.

9 Bd2? loses a pawn. You could drive his knight back with 9 Qa4+. In the game he could counter your 11 Qa4+? with 11...b5 and black wins. Your 12 Qxc4? loses the exchange.

With 16...Qf5? he loses a piece. You are back in the game, you get a good endgame, but you fall to a tactic on your back rank with your pinned bishop.

Your focus should be on two items.

1) weed blunders out of your play. I recommend to switch on move confirmation. Think about your move, make it, check it is no blunder, then confirm it.

2) train tactics.

Stop playing rapid games, and practice more classical game.
Very important understanding own mistake, until you make it again...