Let's start with a Test document. File > New. Click on screenshots below.
From your Toolbar, select the Ellipse Tool. Stroke and Fill as desired.
Now, let's say you have inserted a photo into your document but it doesn't quite fit your layout. Resizing could distort the aspect ratio. We don't want that. To overcome this, Shift + mouse click and drag the Corner resize handle of your photo. Pull the image size to where you want it. Release the Mouse first. Then release the Shift key. Otherwise it won't work right.
Nancy O.