Can porcupines shoot their quills? No.

[Reporter]

I used to believe my elders when they said porcupines would
walk a trail and shoot their quills onto bananas  high above to
rot up the bananas so that the bananas would fall down to the
ground a few days later to be picked up by the porcupines.

Little did I know that they meant that figuratively (the meaning was that you could plan something ahead so that it
will be ready when you are ready to use it).

On a plane ride one time, I was seated next to an older Native
American man who told me that dogs would suffer
porcupine quill shots and that the quills would drill deeper
and deeper into the dogs as the dogs tried to shake them off.

True on the piercing power. By "shooting" he also meant
that the quills would leave the porcupines and hang onto the targets.
That wasn't clear to me at the time of that plane ride.

Here's verification from expert observations that porcupines can't
and won't shoot their quills at you in the distance. If you hug and grab them,
that's a different story. But they won't shoot them out like arrows coming at  you.

https://www.youtube.com/watch?v=37mB2n9Rozw