Undertale is an unusual game, since it’s an RPG, but there isn’t any need to actually fight enemies. Instead, players have the option to defeat them with words. This system can be intimidating at first, but Undertale does a good job of introducing that and other mechanics.
In the video below, you can see the first five minutes of the PlayStation 4 version of Undertale. It includes a general overview of the story, introduction to the mechanics and more.