Let me give you a topics list for some reading because you are in grave danger right now of dooming your hair to a terrible fate - being pulled out during your late-night sessions of raw anguish as you try to figure out how to fix your database again. (OK, sometime's I'm prone to exaggerate a little...)
Look up "database normalization" articles on the web. At first, concentrate on college and university sites because they tend to have good articles. Commercial sites will start up discussions of proprietary features in their product whereas .EDU sites tend to be more matter-of-fact. If you use this forum's SEARCH feature, you can just look up "normalization" because we won't have any of the other half-dozen or more other types of normalization in our threads.
In this forum, look up "data model" and see if anything comes up that is useful. Because with Access, you are frequently building a model of your business data flow. You need to understand your business before you make a model of it, so part of your process right now is to be sure you have identified things you will be tracking.
The greatest danger here is to try to organize things like a file folder by year or by department. The "Access way" (actually, the database way) is to have everything of the same type in a pot of its own, but then use a query to pick out the pieces-parts that you wanted for a given problem or question. So you don't have a table for this year or that; instead, you have one table with the date as part of the data you keep in a given record. THEN you use a query to pull out a single year's worth of data. It is a different mindset than typical Excel usage. But trust me, it is the right way to go.