Can not connect Apple Watch Remote app to Apple TV on iMac

I use my 2020 27" 5K iMac with the Apple TV app to watch shows. I have no remote for the iMac itself so I thought to try and link the Remote App on my apple watch to the Apple TV app on my iMac. Unfortunately this does not appear to be possible as the Remote app just scrolles endlessly and finds nothing to connect to. Both my Apple Watch 6 and my iMac are on the same wifi and updated to the latest software. Does anyone have a solution for this problem? Will I have to buy a separate remote control such as an Apple Siri Remote to accomplish this?