How to import an entire Base into another Base


I am trying to understand if there is an easy way of copying an entire base that has many tables into another Base that also has many tables. I think it will easier to create a component in one Base and to ensure that the data summary works for each component and then import a functioning system to create a much larger Base. This is a limitation of not being able to link Bases.
My excel spreadsheet version already has over 20 sheets which is likely to result in a consolidated Base of 50 to 70 Tables.