How do you add a measure to a piano score?
Welcome to the forum @gutchie
Select the barline where you want to insert the measures/bars, to append some select the final barline. Then press SHIFT-B. enter the number of measures/bars and press RETURN
Hi @gutchie, the webhelp (online Manual) is a nice reference for all kind of questions, and it has a very powerful search engine.
For example a search for add measure gives you immediately some links to the various methods to insert bars (so are they called in Dorico), so that you can choose which method you prefer. (One of them is the Popover method, suggested above by @Vadian):
Thank you for responding
Thank you.