When you are getting hosting with a provider you are given storage space and bandwidth that your website(s) can use.
The one difference between the storage for your website and storage for your computer is that websites are much smaller than what you need on a computer. So, 500MB worth of storage for a website is plenty for a website like this one.
Bandwidth is the number of users that can visit your site in a given month. Each user doesn’t use very much bandwidth so 5GB of Bandwidth, for example, is good for a pretty large website.
If you have any questions, leave them in the comments below.