chess openings to play?

I am just a beginner myself, so do not take my word as expert advice, but I recommend the Karo-Cann for black against E4.
At least I enjoy it and it is not too complicated.

Just play whatever moves you think are good, analyze them, and learn from your mistakes. Learning an opening doesn't mean much when you don't have a good grasp on chess mechanics.

So, I have been playing the Caro-Kann and the Ruy Lopez since around 600. Learning the basic mainlines, and more importantly, the themes of these openings, has helped me get to around 1200. These openings are often very positional, (they can be tactical too), and they really hammer home the basics of strategic chess. Personally, I love the Caro-Kann. It has helped me learn how to take advantage of positional advantages such as enemy pawn structure issues, bad bishops vs good knights and bishops, weak squares, etc. However, because of my low level, these advantages don't guarantee a win for me. In the end it comes down to tactics. For this reason, I have added the scandinavian for black. It has the same pawn structure as the classical Caro-Kann, but it is more devil may care in its attitude, and it doesn't lead to the cramped positions of the advanced Caro. Even though I do well and understand how to win in cramped positions, they aren't comfortable, and tactical play is challenging to find. Frankly, the Sicilian is too theoretical for me. It will very easily suck me in to wrote memorization of positions I'll never see, but I plan to play it if I ever make it to around 1600-1800. I think you can't go wrong with Caro or Scandinavian, but the latter is possibly more beginner friendly if you have a strong grasp on opening principles and the nuances that require you to break them.

There is a lot of different opening you can do, depending on whether you are white or black.
IF WHITE: I advise 1. e4 and continue with opponent moves.
Variations
1.e4 1.e5 I recommend Vienna game/gambit/opening
French Defense: Consider the Wing gambit.
Sicilian Defense: Use the Alapin
I do not think anything else comes up often after 1.e4
IF BLACK: Wait for the first move
If 1.e4: Just counter with Scandanavian defense
If Queens Gambit: Counter with Albin counter defense.
I Recommend to learn from the youtuber GothamChess.
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Simplest and most solid for beginners and world champions alike is to defend 1 e4 e5 and 1 d4 d5 as black and to open 1 e4 as white.

Chess is a game played between two opponents on opposite sides of a board containing 64 squares of alternating colors. Each player has 16 pieces: 1 king, 1 queen, 2 rooks, 2 bishops, 2 knights, and 8 pawns. The goal of the game is to checkmate the other king. Chess is one of many great alternatives to video games.
The best opening chess moves are 1.e4, 1.d4, 1.Nf3, and 1.c4. These all attack at least one central square and either develop a piece or make it possible to do so on the next move.

Go on YouTube, look at a few different Openings, and choose the one(s) you think look coolest (Sounds a bit childish, perhaps, but I believe it does work).

I suggest you learn the Scandinavian Defense. The plans are very straightforward and easy-to-play...

If you want to learn the Siclian, then do it!
This 'want' thing, is important! According to the GingerGM in his article:
https://www.chess.com/article/view/picking-the-correct-opening-repertoire
And Sicilian is played at All levels, and is played by the top players - so it's great. here you go:
https://www.chessable.com/short-sweet-classical-sicilian/course/71311/1
It's not complicated! I assure you, I went through 70% of the course.
Sicilian Does have many sidelines, you should know that beforehand, there's even a chessable course only on Sicilian sidelines. Only 3 on them are good, the rest is garbage, but there's Much garbage.
Shankland is aggressive - basically the course is "Classical Sicilian", but you use the fact that you're Black - you wait for White's moves, and when White chooses something other than Yugoslav / English Attack, you play g6 and go for a Dragon Sicilian - super fun! (super checkmating too, if your opponent 0-0-0-ed).
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If you like Sicilian, then Grunfeld or King's Indian Defense is your choice against d4. I don't know whose better tbh.. Playing K.I.D as Black always gets me confused, no matter how much I try to learn it... Sicilian far is more clear.

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