This is a very broad question and needs a little more specificity to get a good answer.

If I understand your question correctly though, it seems like you are asking how your range should differ for flatting 3 way+ pots vs flatting a single open. The answer to this question is going to vary greatly based on the positions of you, and the opening raiser and caller. Also it is going to depend on the type of player who opened the pot initially (is he a 10/8 nit who opened to 4x UTG or is it a reg who opens to 2.2x from MP, CO calls and you are on the button with AJo.

It is very difficult to just give you a 'one and done' type answer but to give you some kind of answer, I'd say that the better price you are getting to your flat, the wider you can call. This is especially true when you are on the button or in the BB. If a nit opens UTG and you get two callers in front of you and you are on the button, playing almost any suited cards and connected cards and all pocket pairs is going to be profitable. You should be careful in 3way+ pots especially at lower stakes though as a lot of people set mine like crazy. My general strategy for flatting pf in 3way+ pots is to flat a lot in the BB as you will be getting a really good price, flatting more pocket pairs and suited connected hands on the button, and looking for good spots to squeeze primary in the SB(I like to not have a flatting range in the SB at all)

I don't know if I helped at all, and if you want to ask a more specific question feel free, but if you're just looking for a chart you're going to have a hard time finding one as it is very Villain, position, and situation dependant.

Offsuit hands go a ton down in value, and against a 3x open you have to fold when in BB with all the ones that is dominated by the tightest of the ranges. Low gapped suited cards also go down in value. Hands that can make nut straights like 54o and 65o go up in value while hands that make few nut straights like J8s go down in value. AXs and KXs hands do well MW while the flush value of a hand like T8s go down. Especially caller with position on you forces you to tighten up a lot while a SB call when you're in BB mostly makes some extra offsuit disconnected hands into folds.

Here is the hands I VPIP in BB in high rake games vs CO 3x open with no caller:

Here is the same with a 10% BTN CC range:

Thank you a lot for your answers, it's exactly what i was looking for :D