Merge Tables in Excel and Highlight Updated Data

I need to figure out how to merge two tables together and update columns. I pull enrollment files from our database weekly into excel. I need to be able to merge a new export file with the file I already have but only add new people and highlight new changes to the data. Also, I need it to tell me who has been removed from the previous week. 

I can do most of this using Power Query, but I cannot figure out how to get it to tell me which cells have changed or are different.

Thank you, 

Erik