How to aggregrate data with multiple tagging

Hi Anonymous 
You can add an index column by project level using the linked method:
https://radacad.com/create-row-number-for-each-group-in-power-bi-using-power-query

and after you'll get the table like :

you can create a simple measure for summarizing only the first row of every project:

Cf_ = CALCULATE(sum('Table'[Cf]),'Table'[Index]=1)

Result :

The pbix is attached

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Hi Anonymous 
1. You need to merge the tables to get 1.
Please check this guide :
https://www.youtube.com/watch?v=m4feUpoDpVI

2. According to the index it is not a part of UI.
you have to create it. I gave the link to the guide in my first response :
https://radacad.com/create-row-number-for-each-group-in-power-bi-using-power-query