KK on the pre-flop , . can u plz tell me what were your thoughts on the turn?

Villain could be going nuts with the case K, or even a worse set. The only thing your worried about is the flush, but would he cap flop with FD? So I like turn raise.
When he donks river though, I think it's just a call. It's more likely now he has a weakish flush, but your getting 1:12 on a decent hand so you can't fold

It doesn't matter whether BB 3bets or not. I mean it decreases the chance that you are still ahead but no matter what happens : You'll see the showdown! He might be doing this play with a flushdraw since he may think that your 3bet is weak and on this board you cannot realy represent a big hand by 3betting. You may consider to have foldequity on the turn but he may also just have Kx and so Turnraise is fine with your set. Even if you are behind against the flush: You still have outs

I think he would have 3bet the flush on the turn and that why i don't give him credit on a flush when he donked the river so i'D raise again. this stop and go play, donk/call donk is very often some pair but just by playing this line it identifies him as a fish he could be doing this with a wide range. well played in my mind!