What will work for you depends on the capabilities of your TV and stereo... and how accessible things are to each other.
If both have RCA jacks - or headphone out on TV and aux audio in on radio - certainly running cables is an option - though often not the easiest thing to do in an RV.
As long as the TV has an audio out (headphone jack) - it can feed a transmitter...
That transmitter can be either FM based (tune radio to preset FM station) or Bluetooth - depending on the radio's capabilities.
FM example: https://www.amazon.com/Doosl-Univers...dp/B018QN4INM/
Bluetooth example: https://www.amazon.com/Mpow-Bluetoot.../dp/B00P20TFWM
(Note: I haven't used either of these specific devices - they are just examples...)
If the available TV outputs don't match the transmitter - an adapter may be needed... (RCA to headphone... changing headphone jack size.. etc)
If there are NO audio outputs on the TV - then you have more of a challenge - but most SHOULD have something.