"float control" Actually it's "draft" control. You have a position control for your 3 point hitch. It controls the depth the plow would run depending on how far you push the lever. It is not "reactive" You set it and it stays at that depth regardless of the load on the tractor. "Draft" allows you to set the amount of pull or "Draft" that the tractor sees. When the two are set properly together, and you do have to set them together, if you are plowing merrily along at your selected depth and suddenly you encounter a hard spot and the load on you tractor goes up, the "draft" will sense the extra load and lift the plow up but it will only lift it enough to reduce the load to the preselected draft. Once you pass the hard pulling, the draft will automatically lower the plow back down to your selected depth. it is a balancing act and takes a bit of practice to get it right.
If you have draft control on your tractor, you will have two levers for your 3 point.