Facing a 3-bet: fold, call or 4-bet

Why do you fold so much of the hand you just raised?

Because opening and continuing are different bars. You open a hand because it is profitable to play when everyone folds, which is most of the time. A 3-bet removes that path: now you are playing a bigger pot against a range that has already shown strength. Most opens are not strong enough to clear that higher bar, so they fold.

The hands that continue split into two jobs. The strongest become 4-bets for value, and a few weak-but-playable hands become 4-bet bluffs, chosen because they have blockers or play well when called. The middling hands that are too good to fold and too weak to 4-bet make up the calling range.

Does it matter who 3-bet you?

Yes, and you can see it in the charts. A 3-bet from the blinds, who defend a wider 3-betting range, meets a wider continuing range from you than a 3-bet from an early seat, whose range is tighter and scarier. The position the 3-bettor will have after the flop matters too: a 3-bet from a seat that acts after you is harder to play against than one from the blinds, who will be out of position for the rest of the hand.

How do you actually learn these?

Not by memorising every grid. The gap between knowing the right play on a page and finding it under a clock is where the money goes, and closing it is a matter of repetition. PlusEV deals these exact spots back to you and returns to the ones you keep getting wrong. The opening ranges these all branch from are in the chart library, and the positions guide explains why seat decides so much.