1. NATO is openly supporting Ukraine and provides intelligence, money, material and everything else Ukraine needs to win this war. The NATO countries have repeatedly said so in public, it is not a secret. Russia is the aggressor, we (NATO) are helping the victim (Ukraine), and the goal is to liberate all Ukraine from Russian occupation.
2. NATO is not directly taking part in this war. For example, there are no NATO planes with NATO pilots bombing the Russians, USAF is not using F-35s to bomb the Russians. That's a different thing. Ukrainians are doing the actual fighting (and a few volunteers from all over the world).
I don't know why it is so hard to understand this, it is not complicated. These are two separate things. NATO is not neutral, but is not directly taking part in this war.
Of course, the propagandists in Russian TV keep saying that Russia is fighting NATO. But everyone knows that if the USAF used its force the fighting would be over long time ago. The Russians can barely match the Ukrainians, they'd easily lose to a NATO air force with modern F-16s, F-35s, etc.
(And yes, USA has implied that if the Russians use WMDs against Ukraine, then NATO will directly fight the Russians. This is also an option. )