Thanks for the inquiry.
If you are trying to access the AV input on the Roku home screen, you will only be able to see the AV input if you have a Roku TV. Otherwise, you will not be able to access the AV input through the Roku home screen, but rather through your TV input.
You have actual TV? A Roku TV!! Apple TV and Fire TV aren't tv's (yes Fire tv are tv nowadays but at one time it was called a tv when it wasn't), where the Roku TV is an actual TV with a screen, and always had screen when called Roku tv.
settings> inputs> scroll to AV input> add it, rename it if you wish.
I found the answer by trial and error. In Settings/TV Inputs, select the A/V input, and select Remove, then Confirm. Once the input is forgotten, it will reshow as an unfinished option in the TV Input menu. Just reactivate it, and it now shows up in the Home screen.
stevek83 THANK YOU!!!
I have spent all freaking day trying to figure this out. I knew it had to be simple, as the Wii tech is old, but it never occured to me to try this. Why didn't Roku provide a working answer? It is their UI, after all. I commend you not only for your input here, but also for the trial/error process. I was ready to throw something LOL 🤷♂️