Magic Forums

About magic,
I know that doing it needs a lot of concentration and stuff but ive also heard that you need magical power, like a power level of some sort, like how would you determine how much magical power you currently have, how do you check that?
And let's say that i didn't have any magical power or whatever then how would i be able to get more.
or do "magical power" even exist i don't mean it in a way that magic doesn't exist but in like power or do you only need a clear mind, good imagination, good consecration, ETC;
Thanks for your time :D