Power onto sensors

Good Evening all,
could anyone tell me how i could add the power usage as an entity to a socket outlet/light when switched on. I have numerous units that actually measure this but some that dont but i know how much they use so would like to add this to the sensor somehow, maybe in code or something. this will have to be done simply as i am not the best in coding.

Thank you

Have a look at powercalc

thank you i shall take a look