don't have
any wi-fi and too much trouble to install it here
But you have internet, why don't you have wifi? When I get Internet (back in Nebraska and same process in Maryland) the Internet Provider (in Nebraska it was same as my landline phone company, here in Maryland it is xfinity) came out and set up a router box so there is wifi all over the house. Actually xfinity has a hotspot nearby so before they came with the router I already could connect to the hotspot wifi.
You should talk to whoever is providing your internet. If it is the same company that you get cable from, you could probably still be able to cancel the cable part of your package and have them provide an internet wifi router (or, I guess you could buy a router and connect it yourself via calling their tech support or something).
I suppose you could connect a Roku TV to whatever line is providing your internet without using wifi at all, but I'm not sure what type of wire cable you buy to plug in. - editing to add...I asked chatgpt and apparently you would still have to have a router to stream content.
I have a Roku TV and mostly I just watch Amazon Video because it is included with Amazon Prime, I don't pay anything extra except every once in a while I just have to have a specific new movie so I'll pay for that. But if you wanted you could pay for extra channels with it.
Also, if you buy a little antenna you can plug it into a Roku TV and watch local channels.
You can plug cable into a Roku TV too, I have a cable box and it has a cord that plugs into one of the ports on the back of the Roku TV. I don't usually watch it tho, my cable (and internet) is included with my condo monthly HOA fee.
I don't know what is the difference between a Roku TV and other smart TVs, I thought they were the same thing (or maybe I just don't bother to take advantage of the Roku features).