You're trying to link them from gmail. You can see them because your computer has access to open your gmail. We can't, since nobody else has access to your gmail.
Follow the tutorial above.
You either have to upload the files to the motorbicycling.com server (which means your photo size is going to be very limited) or you link them from a file sharing site like photobucket, flickr, imgur, etc. Maybe instagram, i dont know. I refuse to use social media outside of forums.
If you want to link it from some other site (again, you might be able to with instagram) then right click the picture and select copy link url. Then, come back here and paste it like this, but without the parentheses: (
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