Or will it be better to learn 5 different openings at a lower detail level?
And what 1 or 5 openings would you then suggest?
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I would recommend against focusing on depth and instead focus on breadth.
There are "famous" openings that people memorize, and there's some value in it. However, you also have to understand all of the points of departure that arise from it. What happens if your opponent ignores your move, and does their own thing. If you truly understand the opening, then that isn't an issue. However, if you merely memorized the opening, you may not know what to do when your opponent doesn't play ball.
A perfect example from my past is the Scandinavian Defense, 1. e4 d5. This is typically followed by 2. exd5 Qxd5. Then there's a merry chase as black tries to leverage the power of having such a massive piece as the queen out in the open, but still having to pay attention to the development of other pieces. Meanwhile, white can develop while attacking the queen. It's a beautiful opening, and I really enjoyed playing it. However, one time I had an opponent who simply didn't go after my queen. He calmly just went about his business. I soon realized that I'd learned how to follow the "main lines" of this opening so deeply that I had never learned how to actually leverage that queen out in the open if my opponent lets me use it. I fell behind on development, and ended up losing. Later analysis with my chess coach showed me that I actually had the advantage when my opponent deviated from the normal lines, but I simply had not prepared myself to leverage the situation when he departed from the main line.
Also consider what your goals are for chess. If your goal is to win a bunch of games at the beginner level, massive memorization of how to beat someone in the opening has value. If you want to learn the game, however, you may need to take a more subtle nuanced approach. You may want to just try things in the opening, just to see what happens. Eventually you will find that these "openings" are indeed best practices, but by exploring on your own you will learn why they are best practices.
What is your level?
For an absolute beginner learning general opening principles (fight for the centre, develop minor pieces, castle for king safety...), tactic training and paying attention not to blunder pieces in one move, will be much more useful than learning an opening.
Also if you play mostly low rated opponents there is not much point studying a specific line in the Sicilian to move 30 if all your opponents know is the first 4 moves of the Italian game.
If you study an opening make sure to not only study the move but also the typical plans which can be for instance typical pawn breaks, exchanging bad bishops and keeping the good one, typical regrouping manoeuvres, etc
Opening theory can be very complex. For a beginner I recommend to start with the main line and not too deep (how deep will depend on the opening). As you encounter side lines in your games or feel that you lose because you are on your own after your main line theory ends, you can always learn more.
Getting away with one opening will not be possible as with black you will have to prepare for at least d4 and e4. And if you are white and start with e4 you need to be prepared for at least e5, c5, e6, c6... As above I recommend to start studying what you encounter most often first and play the other opening s on general principles until you learn them.