What do i need for the Roku?

okay,all i wanmt on it is internet,netflix and MAYBE hulu...just the basics...because my logic is that,if we have netflix then we can het rid of our direct TV and if we have internet on it we can get rid of our suddenlink....it said we have 2 have wi-fi,i understand that part BUT i live in the country soooo wi-fi is kinda hard 2 get....can a air-card connect to it? if so,could u PLEASE tell me ALL i need for the Roku to make it work awesomely? perrferibly,words that i can understand?