[mtoddsmith]

You should be able to break down a front end project by documenting of all the pages and then components they depend on. Then document their flow (which pages link to which and what dialogs / components they open). Then you need to look at how data is managed among all the pages and components. Do they use something like redux for data management? Then how is the business logic is composed and how backend API's are used. Also for a front end project how are styles managed through out the application.

[barbarbar]

This sounds like some very good suggestions.