@Zacu1, sorry, you need a physical remote. Your TV isn't connected to any network, so no app can be used. You either need a remote from the TV's manufacturer (which isn't Roku), a Roku Voice remote, or a universal remote that supports Roku TVs.
Roku Community Streaming Expert
Help others find this answer and click "Accept as Solution."
If you appreciate my answer, maybe give me a Kudo.
I am not a Roku employee.