I've changed my oil and filter today, on Autodata it says that the oil capacity with the filter should be 3.63

I've filled it up with exactly 4.1-4.2 liters until it was full.

On my other 75 Punto, Autodata says 3.75 and it's the same capacity when I change the oil, I still have some oil left in the can.

Maybe a faulty dipstick?

Yes, I know how to check.
When I filled it up with 3.6 litres, there was no oil at all on the dipstick.

I've putted 4 litres, maybe a tiny bit more and now it's on max.

perhaps you checked dipstick too fast as in oil didnt had time to get to sump