Possibly of interest: My First Chess Opening Repertoire for White
https://www.newinchess.com/media/wysiwyg/product_pdf/9033.pdf
https://chessbookreviews.wordpress.com/tag/vincent-moret/
Sicilian Defense-Grand Prix Opening

From your game position i think most likely continuation is: 6. e6 7. d3 Nge7 8. Qe1 (preventing d5) 0-0 9. f5 creating attacking chances... There are lots of defensive set-ups for Black though. I used to play an early e6, followed by d5 when i faced the GPA as Black. There are several Youtube videos about the Sicilian GPA.

From your game position i think most likely continuation is: 6. e6 7. d3 Nge7 8. Qe1 (preventing d5) 0-0 9. f5 creating attacking chances... There are lots of defensive set-ups for Black though. I used to play an early e6, followed by d5 when i faced the GPA as Black. There are several Youtube videos about the Sicilian GPA.
Yes, the biggest problem for me as white is when the opponent plays g6, then there’s not much weaknesses to attack in the kingside

Yes, grand prix attack does not have a good reputation.
Yeah I’ve found out that black can just play whatever and still fend off the attack.

From your game position i think most likely continuation is: 6. e6 7. d3 Nge7 8. Qe1 (preventing d5) 0-0 9. f5 creating attacking chances... There are lots of defensive set-ups for Black though. I used to play an early e6, followed by d5 when i faced the GPA as Black. There are several Youtube videos about the Sicilian GPA.
Yes, the biggest problem for me as white is when the opponent plays g6, then there’s not much weaknesses to attack in the kingside
"No much weaknesses to attack in the kingside" : quite the opposite!
g6 weakens black's king side in a way.
That's why white can go for f4-f5, opening f file and giving some attacking possibilities.
But sure, lines with g6 are considered the main lines because black's set up is the most agressive.

I play the Sicilian a lot, but hate people who use it against me.
Im not sure which anti-Sicilian openings are good, and so I’ve decided to stick with the Grand Prix attack.
How should black defend, and if so, how good will it be? Let me know please, since I want to win with white
Well, I remember, I analysed this position before with Stockfish.
Stockfish suggestion strategy is simple.
6..... e6
7....... Nge7
8.........O-O
9......... Nd4 ( exchange kt and move another kt to locate that square).
I do trust 3500+ Stockfish than any human theories, SF play is not perfect but 99.99% better than any chess players.

If you want to go a bit in depth, I wrote an article on the grand prix attack. Link here: https://www.chess.com/blog/Hypnoticdemon/hitting-300km-h-with-the-grand-prix-attack

Just watch all parts of Grand Prix in ChessMood! https://chessmood.com/course/sicilian-defence-part-1

I play the Sicilian a lot, but hate people who use it against me.
Im not sure which anti-Sicilian openings are good, and so I’ve decided to stick with the Grand Prix attack.
How should black defend, and if so, how good will it be? Let me know please, since I want to win with white
hi, 1200-rated me. Gonna add some stuff for the black side.
The Nc6-g6-e6-Nge7 type of setup works very well. One of the main ideas is for black to play f5 himself, which stops a lot of white's pawn expansion plans. It looks funny, but is effective. You can also consider playing ...Nd4 to trade off some attackers.

The Grand Prix Attack is good when Black has committed pawns to Dark Squares.
The Grand Prix Attack is bad when Black has committed pawns to Light Squares.
If Black has not committed any Center Pawn to Light or Dark and has remained flexible, it is considered best not to risk it as white and just play something different.
———————
So the original post showed White playing 2…d6.
The move 2…d6 is an error.
The Grand Prix Attack is great vs. 2…d6.
All variations are good for White.
I play the Sicilian a lot, but hate people who use it against me.
Im not sure which anti-Sicilian openings are good, and so I’ve decided to stick with the Grand Prix attack.
How should black defend, and if so, how good will it be? Let me know please, since I want to win with white