How do I get back my original document size?

Whether trying to create a new document or cutting and pasting to a blank new document, my document size and font size are only maybe half the size they have always been, even though the numbers on the page guide as well as the font size number indicate they are still their normal size. It’s like everything has shrunk.

Maybe you have change the scale visualization.

Menu/View/Zoom or the slide right-bottom in the status bar.