My teacher explained to me that we volume is an extensive property because it is additive in nature. But he also told us that pressure is an intensive property. Now according to the gas law equation $PV=nRT$, pressure is dependent on volume. Increasing pressure should increase volume. So shouldn't pressure be extensive as well.
From the ideal gas equation,
Now assuming the gas is uniformly distributed over space (has constant density for a given temperature), halving the number of moles will divide the volume by the same amount. Essentially, if we divide the number of moles by any number, we will end up dividing the volume by the same number to maintain constant temperature. So it doesn't matter how many moles of gas you take at a given temperature, you will always end up with the same pressure. You could also look at it as ratio of two extensive quantities will always give an intensive quantity.