As I'm still unable to add screen shots to forum posts I have to do this as a link to an image on Google Drive. I hope it works.
https://drive.google.com/file/d/1aABcWxnxTHtgUFO7z6o-MmPuWg9LbsOK/view?usp=sharing
That screen shot shows the aftermath of the following steps:
With an image in the clipboard (a screen shot):
1. Draw a frame with the Picture Frame tool.
2. With the frame selected, right-click and select Paste as Content
The screen shot now appears within the picture frame. But there's something missing. There should be a second outer handle at the lower-right of the frame. But there isn't.
When that kind of additional handle is showing, moving the picture frame handles can crop the image, though moving the outer handle at the lower right will resize frame and image together without cropping.
Have I omitted some required step? What became of that outer handle?