What is the best opening?

For me I personally play the ruy lopeź or the London if I’m white but if I’m black I play the kings Indian defence

For a single best opening I don’t think there is a clear winner but it also depends on what level you’re at

I’m only rated 430 so I can’t tell you what is a good opening for high level chess but you should definitely learn 3 or more openings and not to just play one forever

I would definitely recommend learning the London system for white and maybe the kings Indian or CaroCan for black

Sicilian for black; Queen's gambit for white. This is only my opinion.

Those are great openings Mergedjuan but the problem is if you’re 600+ you’re opponent most likely knows the Sicilian and the queens gambit is fairly common even at my level but they are very good choices

Ruy Lopez: most played at top level and for good reason so.

1) Nf3 for white. Extremely solid. Wins a lot too. Doesn't lose much.
For black - 1) c6. Can be played against anything white opens with.
And black is following with 2) d5 ... whether Caro Kann or Slav or whatever.
a very important move - but by having his c-pawn up first black is ensuring he keeps a d5 pawn up there. Including to contest the e4 square.
Black could try the same stuff with e6 - but then he is blocking his c-bishop ... like in the French and the 'Orthodox' defense to the Queen's gambit.
And 1) - g6 for black is ignoring the center too much. Like 1) g3 for white - but that 1) g3 is still #5 in popularity for white on move 1. Its easier for white to 'mess around' than it is for black.
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c6 not only doesn't block a bishop - it also mobilizes the black Queen for Action !!
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You see a similiar idea in the Alapin Sicilian ...
e4 c5 and now c3 ...
white intends d4 like black intends d5 in the Caro and the Slav.
if black goes cxd at d4 then white will respond with cxd also - keeping a pawn up there in that Vital Center.
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'Money in the Bank' idea for white in the Sicilian ...
if you're an e4 player and don't intend to change that (although 1) e4 is overrated) ...then after 1) e4 c5 then in addition to the main line Sicilian 2) Nf3 (which is about the most 'Book' opening there is)
you not only have the wonderful Alapin alternative ...
you also have 'Closed Sicilian' alternatives ...
Like 2) Nc3 ...
its 'money in the bank' to know that that's easier to play than 'Open Sicilian'.
And In addition to e4 c5 Nc3!! (with f4 maybe to come soon like in the Vienna)
you have e4 c5 d3 ... also 'closed' because white's d-pawn does not go to d4 to be taken.
But consider Nc3 instead ... Black's f-bishop has been blocked by his own pawn at c5 ...
that bishop isn't coming to harass your knight at c3 ...
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In openings its important to start your studying with 'money in the bank'.
Its 'money in the bank' to know that with basic endings and basic tactics already in place and ongoing - that your learning curve and efficiency of learning is going to be much better that way.
People who only focus only on openings start getting 'lost' as soon as 'the middlegame' starts asserting itself more and more into the position ... however that middlegame is defined.
And both opening and middlegame will be 'extra-misplayed' without endings insights.
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Mistakes are the soul of chess. Not opening moves.
You won't win if your opponent doesn't make a big enough mistake or mistakes.
And to exploit those mistakes you need to 1) catch them 2) know or realize enough on the spot to exploit them and 3) not make a 'big enough' mistake or mistakes yourself and 4) be efficient enough that you don't lose the game on the clock trying to do all of that!
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Does all of that define the 'main issue' of good chess?
No.
It seems that the main issue is - can you play with enough force throughout the game that your opponent is 'pressured enough' for his play to be mistaken-enough or slow-enough that you can and do win.
Enough force.
That's the nitty gritty of tournament chess and match chess and other rated timed chess.

If you are 430 rated, you don't need to learn any openings at all. There are things that are much more important and useful, you should spend your time on those instead. Most importantly tactics, tactics, tactics.

I kind of agree with that. Tactics. Endings. Basic checkmate positions not sequences.
But every chess student is different.
And learners of chess so often in the early stages regard learning the game from the perspective of playing a game and therefore how to start a game.
Which is reasonable.
People want to play.
So coaches take them up on that preference because coaches want to coach and also to get paid.
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But one of the major pitfalls of such approaches is that the student gets shown openings like the Sicilian Najdorf - which many players might regard as the most important opening variation ...
and expert and master coaches who use it a lot for their play and thereby are 'qualified' to teach it ...
but the Najdorf might be Thee Worst Opening for a chess student.

Next: realize that black's play also defines the opening. Not just white.
Yes that's obvious but its often 'bypassed'.
White could try for 'the good life' with the London System (which 1) Nf3 can lead to rather than the more common 1) d4 which can and does lead to a 'London bishop' if white wants it that way meaning black won't be able to prevent Bf4 by white. Not in any good way it seems.)
After 1) d4 c5 ... has black now 'prevented the London'?
White could now play c3 and then how does black prevent Bf4 by white?
Remember chess wasn't meant to be easy or simple.
Its chess - not checkers.
https://www.youtube.com/watch?v=59RSLhdGWQMtwo seconds video without the heavy profanity.

Update: I’ve been trying the queens gambit recently and it seems to work pretty well and if they don’t play d5 then I can just play the London

If they don't play d5 you can still play c4 on your second move or soon.
Whether they play d5 or not - you can safely get your bishop to f4 in many lines.
Issues about Bf4 include - can black attack your bishop with Nh5? Can he make that work? Will white be able to afford h3 at a certain moment - so that if his bishop is attacked he can 'park it' at h2 ?
And finally can black punish Bf4 with Qb6 soon after? - with the black Queen then hitting both b2 and d4 ...
Of course in main lines of the Queen's Gambit - white is not playing nor looking for Bf4 - he's looking for or actually playing Bg5!
Bg5 - a move that white can often make to work - unlike Bg4 for black which is often more difficult or compromising for black.