Hold'em table

Pocket fours on the button are worth a standard open to build the pot and take the initiative preflop.

QTo is a playable hand from the small blind against a wide button 3x open in 3-handed play; calling keeps pot manageable and retains decent equity.

J4 offsuit is weak and facing a raise plus a call, folding is correct.

With queen-high and only backdoor draws on a paired jack board, checking preserves chips and lets me fold to aggression from the preflop raiser rather than bluffing into a range with many jack hands.

Pocket fours are an underpair on a paired jack flop, and seat_2 checked. Checking back realizes equity cheaply without bloating the pot out of position value.

Strong combo draw with Ts Qh on Js Jh 9s 6h: any spade, 8, or K improves to flush or straight. Betting as a semi-bluff gains fold equity after the flop check and builds the pot for when the draw hits.

Pocket fours are an underpair to the paired board and only beat bluffs. Calling 500 needs too much equity against a delayed turn bet that often has a jack or a strong draw.

King-high on the button in 3-handed play is ahead of the blinds' ranges; raising applies steal pressure and lets me play in position rather than limping or folding too tightly.

4-6 offsuit is weak out of position; folding to the button raise is correct here.

K9 offsuit is too weak to continue out of position against a button open; folding avoids a dominated, difficult postflop spot.

6-10 offsuit is weak and out of position value isn't there; folding the button is fine since this is cheap.

96o is too weak to complete or raise from the small blind out of position against the big blind after the button folds.

Jack-three offsuit is too weak to call or open even on the button in a three-handed pot, so folding avoids putting chips in with a dominated hand.

KQs is a premium hand heads-up in the small blind versus the big blind after the button folded, so raising builds value and denies a free flop.

J6 offsuit is a weak hand facing a 3bb raise from the small blind; folding is the standard discipline here.

K7o is a reasonable button open in 3-handed play with position and a king blocker; raising applies pressure to the blinds rather than limping.

KJ offsuit is playable but not strong enough to 3-bet out of position; calling keeps the pot manageable while seeing a flop cheaply.

42o is far too weak to continue against a raise and a call, even with pot odds. Folding saves chips for better spots.

I have no pair and only backdoor draws with Kh Jd on a 7d Td 2h board, so checking and seeing what the raiser does is best.

Middle pair of 7s with king kicker is likely ahead after the preflop caller checks; a half-pot bet gets value from draws and worse pairs while protecting against overcards.

Weak offsuit-ish hand (T3 suited, low connectivity) from button facing a raise is not worth defending; folding preserves chips.

Q7o is too weak to continue out of position against the big blind after the button folds, so I give up the small blind rather than call or raise.