Ordering switches and kind of confused with relays… Help!

Ok I so far I have a dome light, Totron 30" LED Light bar, and going to have 2- 3" cubes mounted top center of cage for backup lights. I’m getting ready to order switches and I’m kind of confused about relays. I see these "HELLA, ISO WEATHERPROOF RELAY" that look like a good fit for my application being there subject to moisture? I’m not 100% sure if for the little LED dome light I would need to use a relay or not and I’m assuming def need one for the LED Light bar and the LED 3" cubes? I’m still trying to research wiring these up as it’s been a very long time since I’ve used relays, but as I’m going I’m starting to remember everything.