Before answering the question, in hopes of a photo, I went to Google photos. You open up your photos, click on one, the right-click on the photo and select "Copy Image Link". Come back here, click on the 'image' button at the bottom, clear the field when the input box comes up (usually just shows https:// on the left), paste the link you copied (which will be long) and then click on "Add" at the end of the input box.
I've inserted a photo this way just below: