Clarification : Reverse Camera Install with RNS Clone - Wiring

[Broomy]

Hoping the mk5gti massive can help a brother out.

Just bought this android rns clone Android 5.1 CAR in Dash RADIO DVD Player fit for VW Jetta Passat Golf Polo Tiguan Quad Core System DVB-T OBD2 DAB+ Mirrorlink https://www.amazon.co.uk/dp/B01IR2TWBK/ref=cm_sw_r_cp_api_MUAozbAG7617D

Along with this camera (one with the head unit is too bulky) https://www.ebay.co.uk/itm/291016582236

I've been reading numberous guides and YouTube videos but what I can't get right in my head is...

Can I use the wires from my old number plate light to power and ground the  camera? Or does it have to be reverse light?

If it's wired to the number plate bulb does that light have to be on for the unit to activate?

Will canbus take control of screen switching to rvc when reverse is selected? Or is it wired to reverse light bulb for this reason?

Any help greatly appreciated as always