Torso angle mostly depends on the bike's proportions. Most folks ride with maybe 10°-15° of elbow bend. Actually most folks ride straight-armed, but that's not how it's supposed to be. The elbow bend is to absorb shock. So however that works with your bike is how it should be.

Exactly where one sits on a saddle depends on the rider, the saddle, the terrain, and the intensity of the effort. I wouldn't worry too much about it now. Just ride. As you accumulate hours on the bike, your ideas of what your fit should feel like will change. Just keep coming back to those basics of balance, leg extension, and bar position. One's ideas of what's correct for oneself in all these categories normally changes with time, even decades of it. I carry an allen wrench in a jersey pocket when I'm in your position and never worry about stopping to fiddle with something. Keep fiddling until it feels right.

Where one sits normally on the saddle can vary and is the reason for the heel-on-pedal idea of saddle height. Ideally, one should be able to pedal very slowly, heels on pedals, with the leg going completely straight at the bottom of the stroke, yet not losing contact with the pedal or rocking the pelvis. That's usually about right, but "about" is a meaningful word there. Saddle height adjustment from that point is a matter of millimeters up or down until the pedaling action feels smooth and strong.