How to access the data from column of one sheet and then create a connection for logic

This code is to mark attendance from the zoom master excel file.

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After the execution of the data, the file that I recieved is this.
But the issue is that many of the students having siblings shares one laptop uses the id thus due to this one of the sibling is marked absent as they are not using their own id. So I decided to use the siblings data in one sheet and create a connection such that if the students father name is the same as anyother student in the sibling sheet mark his attendance as present.

Im confused how to do it.