GoKawiilRoku TVs can act up for all sorts of everyday reasons, just like any other TV. They may freeze up, stop responding to the remote, disconnect from Wi-Fi or play dead after a software update. This isn't a knock against Roku, just a basic observation that most TVs will eventually try to skip out on you, usually when you're really excited about watching something.
A basic restart is the least disruptive option and usually does the trick. A factory reset, however, is the nuclear option, erasing all of your personal preferences, removing your Roku account and downloaded apps and returning your TV to its original, out-of-the-box state. Fun stuff. Regardless of which extreme you end up with, make sure you have your Roku account email and password, Wi-Fi information and any other login details or PIN you need before the tinkering begins.
For a factory reset, you will definitely need that information to activate the TV and reinstall your streaming service afterward. If the TV is linked to someone else's account, make sure you have their credentials. With that being said, here's how to restart your Roku TV, whether your remote works, the TV has lost internet or it's completely unresponsive.