what's the best opening for 1000elo?

The Scotch and the Ruy are both excellent options, and I’d recommend either one for anyone to use. There isn’t a best opening, though.

IMO or IMAO

1 : 1) e4 e5 since a lot "newbies" plays often this it may give the illusion that 1)...e5 is not very good but in reality it's rather the "newbies" who play badly.

Spanish Opening and Italian Game are the two big weapons used by GMs like Magnus Carlsen, Wesley So, Maxime Vachier-Lagrave so there's no need to talk about it but as a "newbie", foxes do a lot of different things to us that can annoy us :

a : 2) f4 can lead to wild or dangerous positions but we'll simply play 2)...Bc5 and it's ok (of course if we play against stronger than us we will probably lose but we won't feel the defeat due to opening or "they ripped us off")

b : 2) d4 exd4 3) c3 can be a very dangerous gambit 3)...d3 and it should be fine.

c : 2) Bc4 Nf6 3) Nc3 we are tempted to play 3...Nxe4 (with idea 4. Nxe4 d5) but mistake since it's just what the fox wants us to do because after he doesn't play 4) Nxe4 but 4) Qh5 that leads to wild or dangerous positions. We just transpose or play some kind of Gambit King refused 3)...Bc5 4) d3 Nc6 5) f4 d6

d : 2) Nf3 Nc6 3) Nc3 Nf6 4) Bc4 same thing and after 4)...Nxe4 the fox doesn't play 5) Nxe4 but 5) o-o Nxc3 6) dxc3 (and for ex. with Black Levon Aronian perhaps took the biggest slap of his life against Nodirbek Abdusattorov in Aimchess rapid). We'll simply play 4)...Bc5 and it's ok

e : 2) Nc3 Nf6 3) f4 and I don't know 3)...d5 is the mainline.

2 : 1) e4 c5 I find it difficult as a "newbie" and the sidelines much stronger.

Afterwards if we play 1)...e5 then with a better level we end up changing to 1)...c5 maybe it is better to directly play 1)...c5 because we'll save time by not changing the opening.

I mostly agree with the Tiger. I'd say play 1.e4 openings in the order they were popularized, there is a reason they are still around today, they are sound. So play the Bishop Opening or Center Game until you are around 1300--1400 Elo, then play a gambit for the next 600--700 pts or so.

You use the Scotch or the Ruy Lopez, and they seem to be working, as you've reached the milestone with it. Why would you want to change something that is working?

Instead, a good idea would be to work on something that is your weak point. Is it endgames? Defending? Tactics? (Yeah, probably tactics.)

bro you can play the exchange or d4 lines or even just the mainline, you’re allowed to play an opening that has more theory. gatekeeping’s just unhealthy

opening principles are enough

Play the Naidorf against 1 e4 and the Grunfeld setup against 1d4 and others! Get started early to greatness!

I'm amazed at how many different ways the same question is asked of what to play ... do a 3 hour deep dive into opening research on the internet .... not videos .... written words and determine what your goals are with chess and how you can best achieve those goals!

You can play at a 2000 ELO level with the Englund Gambit, Grob, and Halloween Gambit, just by understanding chess better than your opponent, but those openings OTB will not get you very far to often.

Your opening choices probably will follow "YOUR" character traits, not someone else's.

Or just play the "Triple Lindy Double Dutch" reverse reversed!!