Yeah, the packer is two pieces of meat in one. The flat and the point, connected by a layer of fat. You can seperate them, which is what the butcher did to give you the flat, and the point is usually left for burger. I've never seen just a "point" for sale, but lots of flats!
To cook your flat, hit it with some rub (just salt and pepper is a nice start for a first brisket I think) and cook it to 195 internal. If there is a layer of fat on it, leave it on there while you are cooking it. If there is no layer of fat on it, you may consider rubbing some oil on it before the rub and maybe even foiling the flat when it hits 160 internal, and busting it back out of the foil after the temps starts climbing again after it stalls around 160-165. Let it rest and slice against the grain.
I do not normally smoke flats, so maybe someone wtih a lot of experience with flats can give you a better cooking method. I prefer packers because my favorite part is the burnt ends, which I make from the point. I buy flats and grind them up for burger though, adding in bacon for the fat. Yum!