Picmonkey used to be my free pic editor of choice but they have now started charging.
I have found ipiccy to be a brilliant replacement - it's run by the same picmonkey folk so it's transitionally headache free too!
Here's the link if anyone wants to have a look.....
https://ipiccy.com/feature/picmonkey-editor-alternative
a picture paints a thousand words it is said and for selling stuff good pics contribute a huge amount to success or otherwise - so a little time editing can make a huge, huge difference!