Yes and no.
The heater, or more accurately, the blower, will defrost windshield with outside air, heated or unheated. (Its air intake is beneath the cowl vent). The blower will also route air to the footwells, front and rear if the upper right lever is to the right.
The left round vent will give you either outside air, or blower air (depending on the lever position to close the intake flap) and if your car has A/C, there is a duct running under the dash to that left round vent too, so in theory you can get cooled air there too.
The right round vent will give you A/C, along with the obvious under dash A/C vents.
The A/C unit doesn't send air to the windshield...
Not sure if that helps...