With ~10.7BB SB vs BB, Q6s should usually shove pre; postflop, check more on K65ss, and versus the small turn lead on 7s, middle pair should continue rather than fold.
Flop Ks-6d-5s is very connected and BB has the nut advantage; with SPR ~3.9, strategy leans heavily toward checking our range. Betting small with 6x is okay but not preferred—checking keeps our range protected and avoids getting check-raised off a medium-strength hand.
Note: Firing a small c-bet on this wet, connected board is slightly lower EV than checking; checking our range here is preferred.
Turn 7s completes the spade flush and the straight; BB leads 2BB into 6.5BB, giving us about 3.3:1 and requiring ~24% equity. Middle pair still has decent showdown value and some equity versus missed draws, so folding is too tight—calling is the higher-EV option.
Note: Folding to the small turn lead on 7s is too tight; with ~24% required and decent showdown value, middle pair should continue.