On a RokuTV, go to Settings/TV Inputs and look under "Inputs not being Used". Select the appropriate Input that your DVD player is using and select "Set Up Input".
You should now see the Input on your Home Screen. To rename the Input, just go to Settings/TV Inputs and select "Rename" after highlighting the appropriate one.
If your RokuTV remote is actually broken (ie. not working), you can either download the official Roku remote mobile app onto your phone/tablet and use as a remote, or purchase a Roku Voice Remote or a universal streaming remote compatible with RokuTVs from Walmart, Target, Best Buy, etc.
Roku Community Streaming Expert Just another Roku user... I am not a Roku employee. Insignia RokuTV, Ultra 4660, Premiere+ 3921, Express 4k+ 3941, Streambar 9102
By the way, in addition to what @AvsGunnar said about Roku TV devices, if you actually have a Roku device (box, sound bar, stick) attached to a TV, rather than a Roku TV, then what you're looking for isn't possible.
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
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