The other way which may be easier but does not render a high res photo is

Use the full editor
In the grey section at the bottom of the window you will see Attachment Manager
Click on Attachment manager
It will open another window and allow you to drag and drop from your computer or use a file select a file
Once you have completed that hit done
And you are finished.
When you post your response the picture will be attached at the bottom

And now Winterstale you are in the game... and I am clueless