Ouch!
Ohm's Law is R = V/I, P = VI
I haven't been on this forum long but I see the same problems in other forums.
The art in asking a good question is to express the problem as clearly as possible and to give all relevant parameters.
Ask a good question, you get a good answer.
As for the original query, the only requirement is to have an inquiring mind and the determination to find the answers.