about choosing my repertoire

#7 The difference between 1.e4 and 1.d4 is that e4 results in open games and d4 results in closed games. (Most of the time)

thank you very much @achja and V1chess. yes i am not a begining player (you can watch my games ). but i want to know what to play as black .

Just try some different stuff and see what suits you best. Really, this is not up to anyone else but yourself to answer. Most if not all of the information about openings available to us is also available to you. For example, you could use the chessgames.com opening index to make up for a lack of imagination as to what (new) openings or variations to play. I used to do that. There are also hundreds of threads created on every imaginable opening possible on Lichess. Once you find an opening which feels natural to you, you can delve into the literature which will deepen your knowledge of that particular opening.

So, try stuff yourself, use opening indexes to broaden the horizon of possibilities and see what openings and variations come natural to you by actually playing them. Then search for books/videos on these openings. Good luck, and more importantly, have fun!

@LM F_D89 thank you very much .It's very logical and interesting to try your approch !

We've established that as white, you will probably stick to the e4 opening. So, you are basically asking how to best reply to white's openings. White has 20 possible openings. Lets start with the most obvious ones.
1) e4 e5 (King's Pawn Game)
2) d4 d5 (Queen's Pawn Game)
3) Nf3 d5 (inviting to the Queen's Pawn Game)
4) e3 Nf6 (inviting to the Queen's Pawn Game)
5) d3 d5 (inviting to the Queen's Pawn Game)
6) Nc3 d5 (inviting to the Queen's Pawn Game)
7) h4 d5 (inviting to the Queen's Pawn Game)
8) h3 e5 (inviting to King's Pawn Game)
9) g3 e5
10) g4 d5
11) f3 e5
12) f4 d5
13) c3 e5
14) c4 e5
15) b3 e5
16) b4 e5
17) a3 e5
18) a4 e5
19) Nh3 d5
20) Na3 e5

As you can see, you are inviting your opponent right back to the familiar King's Pawn and Queen's Pawn openings.

I agree with the try stuff yourself. If you listen to others you are only doing yourself a disservice. Also maybe you should get your rating established. Knowing the approximate strength of a player can enhance a suggestion.

For example: These will go by lichess ratings as how I view them vs OTB ratings. This isn't a conversion table.

A player between 0-1400: You should never worry about opening play. Learn simply principled chess.

A player between 1400-1800: Focus on mastering principled chess and trying out all opening first moves to see how the positions feel.

1800-2200: Study pawn structures rather than opening moves. And it would be best if you tackled systematic study like "Pawn structure chess" by Andrew Soltis or an opening book based on pawn structure teaching. A real good one is "Mastering the spanish" by Daniel King.

2200-2500: You probably know the opening systems you want by now through the process I speak of. Now it's time to buy specialty books. A good example of those would be "Grandmaster opening repertoire". After 2200 you not only can read those you can start to master an opening. These books are getting extremely extensive. The ones I bought vol 2 and 3 focus on queens gambit positions where you play g3 systems. Very handy.. I have seen interesting black ones as well that I will probably buy very soon.

After 2500 you're probably approximately NM strength and you should know what you want and have a decent foundation. Principled chess is important for everyone, and the fact that it is widely ignored is sad because it would help people learn opening play easier. There wouldn't be questions like this. It would just be known by inertia of this way of learning.

Hope this helps.

thank you very much !

I recommend fully to play all openings. But play one exclusively then move to another and still play the old one you learned. I play d4 e4 and c4. Its best to learn all openings since some can change into others and you can often barrow one idea from another opening to use in others.

Personally, I feel 1.e4 requires White to know a lot more opening theory. If you enjoy studying opening theory and keeping abreast of the latest novelties then 1.e4 is for you.

If you dislike (or not very good at) memorizing variations/systems (like me) then you will probably gravitate (like me) toward 1.d4.

Probably an oversimplication but thats my opinion.

For start try http://www.chesspersonality.com/ to find where to begin.
Dont give up whatever opening you have choose for start, even if your results are not so good. Watch over GMs games and find a player that his games is fun to you, then adapt his opening repertoire.
The opening isn't so important as you think. The must importart is to learn the 10 golden rules of the opening stage. Don't make standard moves, always respond according to your oponnent last move and your general plan for the middlegame. I have beaten 2100 fide elo OTB without repertoire. Even until today I haven't read any specific openning book or have I memorise the 15 first moves, but always after a lost or hard game is see where I was wrong.
But I must say that the openning it's very important for bullet or blitz games, there if you haven't a repetoire you are 70-80% lost against a preperated opponent and the big reason is the time.
The #16 post is very good to remember it.