Hi, Larry, I don't know what kind of software you have but, I think most computers still include the Paint program.
Those instructions are below. Below that are instructions for the free programs Inkscape and Gimp.
Good luck and God Bless! Spirithorse
Paint
right click the photo and point at open with, and click on paint,
Click on the rotate listing and click on rotate horizontal it will work.
Inkscape
https://www.bing.com/search?q=can+you+mirror+an+image+in+inkscape&form=EDNTHT&mkt=en-us&httpsmsn=1&msnews=1&plvar=0&refig=32e37a2fce3545cbb92c034afdb15d51&sp=-1&pq=can+you+mirror+an+image+in+inkscape&sc=1-35&qs=n&sk=&cvid=32e37a2fce3545cbb92c034afdb15d51
Gimp
https://www.bing.com/search?q=can you mirror an image in gimp&qs=n&form=QBRE&sp=-1&pq=can you mirror an image in gimp&sc=1-31&sk=&cvid=BF2D0E02BA08437890832A501F7A7777