I do competitive bullseye rifle, and I've done some basic marksmanship coaching. That's about what I'd expect for maybe 6-12 hours of total training on a rifle for someone with zero prior experience with guns.

The basics of rifles is very, very simple. In competition world we just get overly focused on stuff that doesn't matter - our benchmark is like 10/10 shots at 400 yards in an 8" circle. For someone getting basic instructions, 5/10 shots at 400 yards in a 16" circle is probably fine, and that is an order of magnitude easier to teach.

It took me like 3 hours from zero experience to get to that, and another 300+ hours to get to competitively decent at prone (I might be good now but I'm not particularly skilled so it took me a lot of practice). And we're not going to talk about standing because in the competition world what we do is so far removed from reality that it's not worth talking about in this context lol. Someone with run&gun experience can talk about that, I don't know anything about that.