preflop call is terrible bro, sorry. You can 3bet if you think OR is opening too much, I'd have no problems with that even if it didn't work out, but ATo is honestly a terrible hand to flat vs 3 players.

Just in case, if you're not aware of the concept of "reverse implied odds (RIO)", now's a good time to look it up.

Thanks for your fast answer! That was my inital thought, i would problaby just avoid playing that hand and tighten up the range on flat calling there, what hands would you suggest would be okey to flat call with?

If everyone had 50BB like you, the maximum I would flat is suited aces, suited broadways, and PPs. Set mine or draw to the nuts. Stuff like 65s are too likely to be drawing to a 2nd best hand, but with only 50BB you're going to have to raise/jam flops. But there are two problems in your particular spot:

1. OR (original raiser) only has 22BB. So you're not getting good odds to play any of the drawing hands. He's going to stak off with TP/OP and won't give you the correct odds to chase if the others fold otf.
2. Related to point 1, drawing hands like JTs/Axs, they need two things to break right for you: deeper stacks, and an opponent who has a hand strong enough (and he's willing enough) to stack off with it. So while it's nice that others have come along for the ride, none of them have shown they have a hand worth a lot of chips. It'll take a stroke of luck for both of you to hit the flop hard enough to get 50BB in, and that you're ahead since set over set or draw vs better draw are always possible. (which is why there's no shame in mucking baby PP like 44-22.)

I don't know your background (tourney vs cash), but the fact is, tourney poker is short stack poker, and frankly, unless you're a math geek, the "poker" part can be pretty boring. (I happen to love tourney poker, though I mostly play cash.) It's really knowing spots to shove and when to call shoves. In your hand, so much would depend on the opponents, the buy in level, and the stage of the tournament (all good info to include in your post...I can't even find the blind level, so I'm assuming its 200/400/50 or so--if no antes or if only 150/300 your shoving range should be smaller), but here's how I read your spot: The two big stacks could have iso raised a shortie but they didn't, so they don't really have strong hands in their range. So if you think that the OR is either a bit too wide, or a bit too tight and has a fold button, I'd much prefer a jam than a call. If there's antes, add that to the 2 flats that will almost certainly fold to your jam, and there is so much dead money that combined with a bit of fold equity (FE), this is a great jam spot. Off the top of my head, you'd be putting in 22BB to win about 50 when you're called, or pick up 9 BB right away. It won't take much FE to make a shove a profitable play here.

Don't think there's any need to call pre flop with such a marginal hand, not gonna love life if we spike a A. Flop looks like a fold when there is one overcaller, what are we really hoping happens on the turn and river other than checking through? Have to fold to any turn bet.

It's a hand you'll have a hard time playing in a multiway pot. A 3-bet from one of the three players still to act behind you is also a possibility with so many chips already in the pot. So I doubt flat calling is the most indicated action in this spot (flat calling range has been mentioned above). 3-betting yourself is in play, but more info about the OR is needed.

How do you interpret their small bet on the flop combined with the shove on the turn?