ROKU uses your computer’s ISP.
You will need high speed internet, broadband. We have a wireless router which is used by our computers. Our ROKU is hooked into our tee vee (Samsung- Smart TV) and we are then able to watch the shows on our tee vee in the comfort of our living room seated, sprawled on our easy chairs :)
The ROKU comes in several versions. The least expensive being $40 (ours) and with more features come the higher costs. Believe there are now 4 or 5 versions of ROKU on the market.
Ours allows us to search and watch anything on YouTube, as well as the various stations.