Finding a duplicate and assigning a set number

Hello All,
I am new to macros. Need some help in solving the following scenario..

Suppose i have 10 records with duplicates in it based on name.
1. I want the set number column to be filled with a value starting from and then increased by a value of 1.
2. In the other column Master. I want one record from that duplicate set to have a value yes.

Something similar to this
First Last Name Phone ID Street setno. master
C d 123456789 123456789 abcd 1 yes
C f 1234 12345678 abcd 1
A d 123456789 12345678 abcd 2 yes
A d 123456789 12345678 abcd 2


Is this achievable???

Thanks in advance..

I was succefull in creating a set number but here comes the real part
how do i assign one of them as master record based on some condition like if phone no <> null, Email <> null etc