I have my old player, no remote. I have a new WiFi router so no previous connections. I’m trying to manually enter my ip address in the app to use as a remote. I’m out of ideas
How old is the Roku? You can buy remotes at Walmart and similar. But then, it may be cheaper to simply buy a new Roku. A new one may also be much faster (my recommendation is to NOT get the basic Roku Express. The Express 4K+ should be the base model.) If you tie it to the same account you used with your old one, all of your apps will automatically install. You just need to rearrange them in the order you want. Some apps may require re-logging into their services.
Just to be clear, if it was ever connected to Wi-Fi in the past, then there is a previous connection, and if you know the SSID/passphrase, then you can use that. (The previous connection trick is putting this info into the new router, not the roku.)
Until the Roku gets connected, it doesn’t have an IP address. It doesn’t even know the local private address range that your new router might be using.