Disc, disc harrow... All the same. The differences in name is a regional thing.
As far as will it level? Depends. Different brands do better job than others. Older John Deere disc's are known to "ridge". They leave a furrow on the outer extremes, and a pile of dirt in the middle. Older International Harvester discs do a MUCH better job in that regard.
The biggerst issue with a disc is getting it to cut. There has to be enough weight to get it in the ground. Most light-weight 3-point discs suffer in this regard.
The only remedy, besides packing on lots of weight, is to go over and over the ground until it's worked up. With a disc that doesn't do a good job of leveling, that leaves you with a rough surface.
I drag a piece of 6" schedule 80 pipe behind my disc. ( Old IH wheel disc) It's 2' wider than the widest part of the disc. (It's also full of concrete) The pipe, with it's added weight, smooth out any ridges the disc leaves behind.