Are you talking about the camera views? (I.E pressing the 1,2,3 buttons on keyboard?) or "free camera mode"
For free camera mode
Go to the Documents folder / My Documents / ETS2 and then click the “config.cfg“, this opens it now with the text editor. Now you look for the entry “uset g_developer” and “uset g_console” and change there the “0” to “1“.
The speed of the camera: “uset_g_flyspeed” 100.0 ” it is best to “100.0 ” Editor save, done! In the game you then press the “0” for free camera and the arrow keys 8,4,5,6 in the numeric pad on the keyboard and the mouse movement.