Replying to Laptop

So I just enrolled in a high school online class. It's a semester class and don't have a laptop to use for it. Right now I'm using school computers and my families desktop but having a laptop would make it 100x easier since I could work on it from anywhere. The issue is I only have around the $800 range to spend. I would like to have word or pages, PowerPoint, and excel. This laptop I will use in college starting next year and need it to last for another 4 years. I know $800 isn't a lot but thanks for the help in advance! Any stores you recommend looking at please say