Question about K712 Pro - 102882

Should already be amplified, as it needs a little more power thanks to the impedance.

If necessary, you can also connect it directly; but it's like driving on the motorway without a turbo. It works - but it's no fun. If you buy headphones in this class, you really need at least a simple amplifier/DAC. You don't have to spend 1'000. It depends on whether you are satisfied with 90% - the last 10% cost 1000% more.
Only you can decide whether that is enough for you and your ears.

This should also work fine directly with the computer.