Creating a summit rest

In the picture I have attached, there is a quarter rest placed above two whole notes in order that three quarter notes (all on C) follow the whole notes(F,A) in a single measure. (4/4)

The method of inputing a triad or diad of notes is only possible using the mouse--using the shift key with numbers and letters does not work. Therefore adding a quarter rest at the same moment in time as the two whole notes can only be done using the mouse, yet the rest always is placed after the two whole notes.

Is there a special designation for a rest occuring at the same time as notes?

Please forgive me for my ignorance of vocabulary. I am learning piano from a Frenchman here in Germany.
Kapiert?