I am want to buy a picture for my website, once I purchase it can I directly download it to my pc and then upload it to my site?
Yes, once you have it licensed you can download it and have it on your site. As long as you aren't selling the image.
Here is the copy of the licensing information. http://wwwimages.adobe.com/content/dam/Adobe/en/legal/servicetou/Adobe_Stock_Terms_en_US-2 0150313_hpc.pdf
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