66 river

He raised us small on turn, I would put him on TP or smaller overpair so I wouldn’t go big with my river bet. 1/2 pot is Ok in my opinion, maybe up to 2/3.

He had T9. But I don't understood how he had play his hand.

My god please don't donk that turn (and that river) ! Learn to check also when you have it or you'll get crushed.
As played him holding T9 is totally fine, I don't see the problem with it.

Ok : check call the turn and bet half the pot at the river.

I think it is a good spot to loose some chips if a random card fall at the river.

Ì don't get the point for the 1/2 river bet. I would check the turn. But as played he now has straight or better, or nothing, so he is either calling or folding to any bet. Shove the river, yes he might have better hand than you, but you can do nothing in this case, you'll always loose your stack.-

x/c OTT and x/r OTR or just shove, depending on what you think is gonna call and bet himself if you check.

Yes, I would also X/C turn and shove or X/shove river now when I know he hed T9. But while in the hand he can have 99, Ah9h, Jh9h. Would you really check and risk to give him free card? And on the river why would you shove? A8, T8, JJ-99 will certenly fold against shove, and can easyly call 1/2 pot, maybe even 2/3?

Of course I'd check OTT "and risk to give him a free card", it's the bread and butter of this game ! You are not here to bet weirdly any time you don't want to give a free card to a small part of villain's range, or else you can begin to bet stupidly pretty much any spot any time.
Firstly, he is supposed to bet his 9x himself.
Secondly, the board is already too ugly, you are in a tricky spot where you are too WA/WB to really want to value (you wouldn't like getting raised etc).
Thirdy, if you begin to get out of your usual way with your sets here you are gonna cap yourself so hard your actual check/calling range will be way to weak. You have already enough of a range disadvantage as it is.

For the river shove, I indeed am in the check/shove team because I tend to allow villain to value/bluff by himself but I have to admit the more you are playing microstakes fishes the more passive they risk to get and you could somewhat imagine them having combos that they're gonna check behind whereas they would have called a shove with those so I get where the donk shoving team is coming from.