Row by Row, Cell by Cell, Return Cell header

Hello!

Just got into KNIME and have started my first project. Taking two large Sheets and Comparing row by row, cell by cell. I have been able to get the Row by Row created and working properly but now am wondering what nodes to use to go Cell by Cell, looking for matches for each column of each row, if no match then I want to return the header of the column so I can understand what has changed between the two data sets.