you can do both for health and power for health/power you'll need to go to each unit frame (player, target, pet, ect.) and set the health/power second text element to enabled and in the text box you'll put [perhp]% or [perhp<$%] and you'll do the same with the power/mana using [perpp]% or [perpp<$%] you can find the text inputs for the text boxes in the help>text tags.
you can do both for health and power for health/power you'll need to go to each unit frame (player, target, pet, ect.) and set the health/power second text element to enabled and in the text box you'll put [perhp]% or [perhp<$%] and you'll do the same with the power/mana using [perpp]% or [perpp<$%] you can find the text inputs for the text boxes in the help>text tags.