2 dead ball penalties after score
 

Team A scores a touchdown. After the touchdown there are two dead ball penalties, the first is on team A and the second on team B. what are all the options on this penalty for both sides?

NFHS - Assuming both DB Fouls happened before the Ready for Play ...
1st - Team B may choose to enforce A's foul on the Try or the ensuing Kick-Off
2nd - Team A may then choose to enforce B's foul on the Try or the ensuing Kick-Off

both fouls happened before ready for play. if both teams wanted to take it on the try is it from the 9 yard line?

Correct. Penalty on A sends them back to the 18. Penalty on B would be half the distance.

... and, if Team B fouls first, and then Team A fouls, you'd have the try attempted from the 16 1/2 yard line if both fouls are enforced on the try.

If both dead-ball fouls happen "at approximately the same time", you offset the fouls and run the try from the 3.

What if there was a holding penalty on the D on a scoring play? Are the options the same? Live ball

Foul by the opponent of the scoring team my be enforced on the try or the subsequent kickoff.

Also on the try???? any foul on a try by the D can be enforced on the Kickoff