When you have your pawns on d4 and e4 and knights on c3 and f3 (with white)?
After 2. ...f6 this is called Damiano defense, and it is pretty bad. 3.Nc3 is a mistake. White should play Nxe5 with the idea Qh5+ next if black takes the knight.
you can check the openings by name and quality here.
365chess.com
When you have your pawns on d4 and e4 and knights on c3 and f3 (with white)?