in excel How do I create a dropdown list that populates a row from a range of 4 columns

Perhaps the following will help.
1. Make a list of distinct manufacturers from column A as modeled in column E.
2. Fill the MFG drop down using the source: =OFFSET($E$3,0,0,SUMPRODUCT(--($E$3:$E$12<>"")),1)
3. Fill the Description drop down using the source: =OFFSET($A$3,MATCH($G23,$A$3:$A$12,0)-1,1,COUNTIFS($A$3:$A$12,$G23),1)
4. Fill the Part Number and Finish columns using the following formula (not drop downs): =IF($G23="","",INDEX(C$3:C$12,AGGREGATE(15,6,(ROW($C$3:$C$12)-ROW($C$2))/($A$3:$A$12=$G23)/($B$3:$B$12=$H23),1)))
Note that the gray area is moved so that it will not be in the way when the rest of the 30 rows are added.
Let us know if you have any questions.

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