A cordless drill/driver isn’t especially accurate. A torque wrench will give you a better result.
That being said, you could try calibrating your drill against a torque wrench and note down the Values. Alternatively you can put a long Allen key (or similar) in the chuck and measure how much weight the drill can lift.
1 Nm equates to 100 grams* at a distance of 1m, as does 1kg at 100mm, 2kg at 50mm, etc.
So if your drill can lift 5kg at 100mm away from the drill shaft, that setting is delivering roughly 5Nm of torque.
*its actually ~101.97, but 100 is close enough for practical purposes.