Neck strikes(Pressure point knockout)

I’ve always wanted to try this on someone,and was wondering if it varies with different types of people.I’ve tried pressure points on my friends once,but only 1 reacted to it,and the others did not. I was wondering if it would be the same for the pressure point strike to the neck that is supposed to knock someone out. I want to know if there is a certain amount of force you use with different people. Like big muscular guys…do they require more force to get knocked out?Or a fragile girl…requires less force? I’m not so sure. Or maybe it’s the same for all types of people,and they all require the same force. Either way…I need to learn how to do this…it’ll give me something to defend myself. and is the vein you’re supposed to hit on the right,or left side of the neck? Please answer…thank you