1.d4 the best beginner opening and not 1.e4

I notice your avatar is from a 1.e4 opening -- Fried Liver.

I do not know how to flip the picture at the time of upload. I like black here. Check my games. I like to bait white into playing fried liver.

All beginners are different. Some of them can have more success with d4 openings, some with e4, and some with something else.

But in general, I would say, that it's better for beginners to play more open games, which usually arrive after 1.e4. I think so because in my opinion beginners should play more open positions to get punished for their mistakes (like leaving their king in the center, not developing pieces, weakening their king, etc.) and learn from them, so they can get better. It's also not unlikely to get punished for those mistakes in a closed/semi-closed game, but it's less likely than in an open/semi-open game.

But d4 for beginners is not a bad option by any means. For example, the London System is a very good opening for beginners, because it doesn't have a lot of theory to study and it's very solid.

In my opinion, Sicilian for beginners is not a good choice. It's a very complex opening that aims for imbalances and tactical play. I'm not sure beginners even know what that means. Also, some lines consist of a tremendous amount of theory (for example, the Najdorf). Of course, beginners can play the Sicilian without theory because almost nobody really knows what they're doing in the opening at that level. But there're much easier ways for beginners to learn chess. 

I think it's better for beginners to learn a simple opening and know that you're playing the opening in a correct (or almost correct) way and focus on improving later stages of the game.

Not true, playing tactical, open positions like in the Sicilian Defence is good for beginners.

You also contradicted yourself saying there's loads of theory but there's no need to learn that theory at the beginner level. When most people think of theory below 2000, it's only up to about move 10. Opponents will not be GMs who know all this theory.

The other reason the Sicilian is good for beginners is because it's the most fun opening in chess and results in super, interesting tactical positions. For this reason, it can be motivating to play it instead of playing something simple and boring like the London or Caro Kann.

Even though there are a lot of people who say this kind of thing "beginners shouldn't play the Sicilian", generally beginners who persist with the opening have great success. It's also about what people know and are accustomed to.

Yes. You are correct but many beginners respond to e4 with e5 allowing for powerful setups like the ponziani opening. I would as a result suggest e4 as a good beggining to a game.

I would also recommend e4 but I wouldn't recommend Ponziani. It has some tricks but I wouldn't describe it as a powerful setup. It's ultimately inferior to the big 3, Ruy Lopez, Italian and Scotch.

The Ruy Lopez is the best as it's the strongest and most ambitious at all levels. It's also good at lower levels as it has a lot of tricks. A lot of beginners play the Steinitz Defence (3. d6) which white does very well against.

White can also do very well against the Sicilian if they learn a proper setup against it like Yugoslav Attack, Richter-Rauzer, Fischer-Sozin Attack, etc. In this sense, it's good to play the Sicilian from both sides as it's a fun game for both players.

I  have played e4 from the beginning but I also play d5 against d4 so I don't feel like I am missing out by not playing 1.d4

Prove yourself right.

h2 the best

e4 goes for more agressive games where you have a better chance at winning, d4 is more for positional games where the chance for drawing is higher and attack is lower

for example: i will compare main lines from e4 and d4

1st is a ruy line, where white will have a kingside attack and agressive play while black will open the position and refute white

2nd is one of the queens indian othodox lines where it can be quite drawish  but is good for both sides

What's there to prove? you haven't made an argument for your position.

I play the alapin as well and in internet chess 2...Nc6 is the mainline and in that position some play d5 and you get the isolated pawn and sometimes they completely mess up and get crushed down the centre

g4 pretty sick icl

The Alapin Sicilian is lame and boring. You say it's great because opponents play Nc6 against it but then your entire argument for it being a good opening is that the opponent plays a bad move against it. All of those variations you mentioned are lame sidelines and much worse for white, especially the wing gambit.

It's not a reason not to play the Sicilian because the fix is easy. Against the Alapin you just play Nf6 or d5. The reality is the Alapin is very unambitious for white as white ends up very passive.

I shot out of the beginner-intermediate range by working on tactics and playing exclusively hypermodern. Perhaps experimenting is a better way to grow as a player.

I shot out of the beginner-intermediate range by cheating

Wow