No worries! If we don't ask questions, how do we learn?
3 point is a seat, a very functional seat - where the rider's butt is very close to the saddle, but not in the saddle. The point where your breeches are just touching the seat.
Your legs are under you squeezing your horse up into your seat at every up stride in the canter, your core is very active, your chest is opened and your upper body is tall. All your bodies weight is in your heels, and your knee's and ankles are absorbing all of the energy.
Two point varies -
Eventers will move into a 2 point, or 1/2 seat between fences. Where you are still using your core to center you, your body is balanced over your feet, you are out of your tack and just hovering there out of your horses way.
I can ride in this position till the cows come home, very comfortable for me.
And then there is the other two point we know of, when over fences.