I finally figured out how to do this, but it is a bit confusing.
When you click the "(some html is okay)" button you will find different ways to add different stuff. When you look down, you will find the image one. Copy and paste that. Then copy and paste the image url, replacing the part that says "https:// www. goodreads.com /image..." You can change the height and width number up and down to size your image. You don't have to keep the alt text, it is just there to show our visually impaired members what the image is.
When you click the "(some html is okay)" button you will find different ways to add different stuff. When you look down, you will find the image one. Copy and paste that.
Then copy and paste the image url, replacing the part that says "https:// www. goodreads.com /image..."
You can change the height and width number up and down to size your image.
You don't have to keep the alt text, it is just there to show our visually impaired members what the image is.
I hope this helped!