Create Custom report

Hello 

I am using SharePoint Onlime

I want to display reports as mentioned below in light green color. I have three type of list as mentioned below in blue colorwith the reference.
In Document list we have 6 type of standard documents, 4 of them are mandatory and 2 of them standard.
Whenever new employee join the organation, these 6 type of document should upload in empdata list as individual item, but some times during joing some mandatory document not available with new joinee.

Now we want to check which documents are missing especially mandatory document, for this we have mandatory type in Document list.
We want to validate generate type of reports by selecting department name and entering employee code.

 How can we set the linking between Empdata and Department and generate above report

Regards

Avi65