Off setting door in tutotial 2 youtube

When I highlight 3 lines for the door as in tutorial 2 on youtube, using the shift key, I can’t perform the offset task it then asks to do, the highlighted lines become not highlighted every time i try…

Are you selecting the right tool, sometimes people mistake the follow me for offset and that will deselect.

Thank you - just double checked and yes I’m using right selection…

What are you doing different to this?
Offset01

You could try it this way, assuming nothing is a group or component. Using selection box first, then deselect parts, then offset.

Got it working by putting curser into red box specifically but feels like ive been doing that Thanks - great help already…