I found I could drag and resize the image, making it smaller, and then could add stuff below it. This was on my laptop.
On the tablet, I've had no luck.
I think, in future, if you choose a resize for the attachment, eg medium size,as you’re posting, , it will give you the space to maneuver in post edits. People can click on the image to see the full size image.

thanks for the info..i will give it a try.

Still on my iPad. Today I tried posting a photo from my imgur account, using the Upload from URL tool.
it kept saying invalid image file, so I copied the bb code option from imgur and pasted directly in to the post box. That worked, but I had a huge image, and I could not get past that black square to add anything else , in the edit screen.
I found after tapping repeatedly on the image, in frustration, another little dialogue box appeared and it had the option to change the size. I couldn’t select a preset size from the dropdown, but I could physically enter dimensions. I put in 500 and it automatically added the correct scale number for the other side. The result was a smaller image that I could then get past and add more.

Hope this helps.