If you don't follow this, you should ask someone with a better understanding of these terms for advice.
For example the basic requirements for a simple WordPress website with a modest amount of visitors without extensive peak traffic are 250 MB disk space and 1 GB data traffic. Furthermore one MySql database is needed and scripting in PHP. Fortunately many providers offer WordPress installation software and comply with these basic needs in their hosting plans.
However if you have many reasonably sized photos, for example: more than 100 of 1MB each or videos of many MBs, then more disk space will be needed up to 500 MB, 1 GB or even more. The same holds when you incorporate extra functionality in your website through plugins.

Step 2: How do I find a provider?
Now the minimum requirements are settled, it is time to investigate which provider suits you best. Apart from make inquiries in your network, you can consult web hosting review sites, like following sites (in Dutch).