Uploading images is actually quite easy. What would help with answering Alice's question correctly, however, is knowing where the picture is wanted. Is it to go on a profile, or is it to post on g2g?
Images for profiles - specifically the main profile picture - are uploaded directly to the profile via the images tab.
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There are other ways to show images on a profile, where the image does not have to be uploaded to that profile.
Adding images to g2g is a different thing.