Help attaching photos

[bluzrulzsp]

I am new to MacBook and have an Air. I am trying to do an ad on Craig's List and can't figure out how to attach the photos I downloaded to it to the ad. Also I don't get how to open the Photos folder up when I get to the documents window. If I click on it a window opens up with the photos logo on it and when I click on it nothing happens. If I double click on the photos logo in the documents window it just disappears. Macs are just so different.

 

[kch50428]

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