I'm kinda a newbie with texas hold'em so need some expert help here

my question is if 2 player have 2 pairs for example...

player 1 have 6d 5d
player 2 have 4d 3d

and the community is As Ah 6c 3c Kh

so basically player 1 have Ace high pair with 6
and player 2 have ace high pair with 3

so who win this hand since they both have ace high pair do you count the second pair?
what is the basic ranking rule for 2 pairs and flush?

question 2.
player 1 have Ad 3d
player 2 have kd 5d

and the community is As 5c 6c 3c Kh

player one have Ace pair and 3 pair
player two have king pair and 5 pair

who wins this hand?

question 3 what if..

player 1 have Qd 3d
player 2 have Qc 5d

and the community is As Qh 6c 6h 2h

who wins?
when does the kicker count for 2 pair or how does it count?
does texas hold'em always goes by best 5 card rule?