Auto populate data with a drop down list

The best way to do this is to format the whole range as a table and use the autofilters built into the table (the little down triangles added to each header). I'm suggesting this method specifically because the last line you say "The rest of the fields would be left to be filled in manually." and although you could use pivot tables with slicers and such or data validation drop down menus, those will only display the resulting 'filter'. In order for you to ENTER DATA that will stay with the corresponding names you need the whole thing to be a table and then filter the relevant lines and then you can enter the data on those lines. I hope that makes sense. If you need more help please attach a sample sheet and I/we can tweak it if needed.