If (or when) NATO is directly fighting Russia, NATO will be composed of the US, Canada, Ideland, Norway, Sweden, Finland, Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Hungary, Romania, Bulgaria, Turkey, Greece, Solvenia, Croatia, Montenegro, Albania, North Macedonia, Italy, Germany, France, Spain, Portugal, Luxembourg, Belgium, Netherlands, Denmark, and the UK (I might have missed some).
One way to tell this story is that "Russia can't possibly win a war against all these countries! There are so many countries in NATO!"
Another way to thell this story is that "Russia's enemy is already divided."
Being divided into 30 some odd nations doesn't make NATO more powerful just because 30 is a bigger number than 1. It's actually far less powerful to be divided.
A better way to compare these powers is to compare actual capabilities: Tanks, artillery, soldiers, fighter jets, etc.