Ah, I see! The general equivalent of Areas in OmniFocus would be Folders.
For example, I have an Omni folder, with all of my work-related projects going in there. Similarly, I have a "Personal" folder that holds the majority of the remaining projects. (There are a few sub-folders in both of the ones I mention to supply some more organization.)
You shouldn't need to create contexts for each of your projects, though. That's going to create a ton of clutter that won't actually help you get things done. Based on your description of your current workflow, it sounds like you're mostly going to be working out of project mode. I wouldn't worry about contexts at all yet. You're likely to want to learn about it later, but for now I wouldn't sweat it.
If you want faster access to some of your important projects, I'd suggest flagging them, then using the top-level "Flagged" list as a shortcut to jump to those items. To flag a project or action, tap it to bring up the editor, then tap the button in the lower left of the "Info" tab.