Newbie questions

[ilyazhito]

A face mask is a spot foul +15, with an automatic 1st down, unless the NFL has both 5 and 15 yard face mask penalties. The spot of the foul on face mask fouls is usually the end of the run, which is the basic spot for enforcement on running plays, because the being tackled by the face mask usually stops the runner's forward progress.
Number 2 is true in NFHS and NCAA, so no reason to suppose it would not be true at the NFL level, unless someone brings up a citation from the NFL rulebook saying otherwise.
Holding is a spot foul, with a 10 yard penalty, so where the hold took place matters. The only exception is that holds behind the neutral zone are enforced from the previous spot.