> How do I access all 3 bands on my router[?]
With three different, suitable wireless devices?
Is there some actual problem which you are trying to solve?
If you visit the support pages:
Support | NETGEAR
you can feed in the model number and find the documentation, and, if there are any, firmware versions and drivers for your hardware.
Just another user.My network DM200 -> R7800 -> GS316 -> PL1000 -> Orbi RBR40 -> Orbi RBS50Y -> RBS40V