I'm trying to make a topic/category like the ones below in bold, where I can place my documents and files underneath to organize everything. I've tried creating a column but it just makes a section similar to the "modified by" or "created by" columns. Could anyone give me some guidance? Thanks!
If you've created the column to classify you are half way there. In the picture, you are seeing a grouped view. You just have to create that which is easy.
On your view, you go to the Library tab of the ribbon and click the Modify View button. On the resulting page, scroll down to the Group By section and select your category column. Click OK. You should be back on your view with your documents grouped like you want.