Thanks for the info bro. I use this calculator, it works great! And how do we subtract half of n from the point X and Y coordinates?, or do we need to get the coordinates x, y from half of n? (if there is, then what are the coordinates of half of n). Or was the subtraction just an example to show so that I would understand?.
OK, tomorrow I'll try to test this key))
You could use offline tools or online such as secret scan dot org or privatekeys dot pw in crypto calculator section.
With java one I linked, you can't calculate addition subtraction of a vector ( public key ) with scalar ( private key ), you can only multiply and divide.
Also my calculation above is not accurate, if we divide 7 by 3 we need to divide n by 3 and subtract the both results to get our answer which is 2. Remember when you do sub, add, if you subtract a -n point from a +n point, you will be adding them, learn - and + ops first.