Is there a way to select multiple program lines at a time on the teach pendant?

I believe you could use the FOLDER command to group lines of code together. Then copy and paste that folder elsewhere in the same program.

Or create subprograms and call those in your MAIN program.

Though these two commands only work with sequential lines of code.

As for something similar to a PC like holding CTRL and selecting scattered lines you want to copy or delete, I do not believe there is a way to do that in UR.

You have to do that one by one. At least that has been my experience so far.