Don't move all of the faces Hey

I only want the face between the red lines in the picture to be adjusted, so that the edges, here marked red, end up where the blue drawn lines are.
Moving the selected face with G did not give me the wanted result.



Here I first extruded the face (selected in the first picture) with E (instead of moving it), but I don't want those edges which I marked blue.

Thanks so much for your help
Perhaps you are trying to extrude the face? This can be done by pressing E with the face selected.

To delete those added lines, there are two ways to go about doing so.

Method 1) In edit mode, press 2 to enter edge select mode. Select the unwanted edges, press X and select Dissolve Edges.

Method 2) In edit mode, press 3 to enter face select mode. Select the faces you want to join together, press F and those faces should be joined together.