Sorry for the hassle. Roku tv’s are great. TV plugged in: check. New batteries: check. TV turned on: check. Can you get to Settings? If so, then you can pair a new $10 Roku from Amazon.
I love Roku TVs. I've got two of them. I love the simple remotes.
These are probably the easiest TVs to set up and you can buy replacement remotes from Amazon for under $10. I always have a few spare remotes on hand because the kids are always losing them.