I got a bow from my friend since he ended up buying a new one. The only problem is he knows nothing about the specifics of it. He doesn't know draw length, let off %, or the amount of pounds. How would I go about finding this info out?

I recommend taking it to a bow shop and let them tell you.

sometimes it is right on the bow. seem wierd that your friend doesn't know his draw length . you migt have to measure it your self witha scale and measure an arrow at full draw. you should also find what your draw legth is so you get a bow that fits properly. have the wrong draw length bow will cause you to not shoot as well as you could

A good pro shop can get you off on the right foot.

You can also look on the manufacturers website. They usually have a section titled 'Downloads' or 'Manuals' where you can downloads previous year's owner manuals.