i emphasize that i am a total newbie and video making stupid. i have a panasonic lumix camera that i am going to use to shoot interviews. i am going to order from amazon, so i dont want to order the wrong thing.

what do i need as far as a mic goes? i just dont get how the sound gets from the mic to the camera. so whether i get a lavalier or handheld, what are the other accessories i need? also, it will likely need to be wireless since i will be mobile. any advice would be helpful