Sorry add to such old post, but I had the same question as Theresa. I just made a BitBucket account and there's a README.md file with tutorial instructions. There's also a video from Atlassian's Youtube account where it shows how to implement the instructions (see around the 0:35 mark here). It seems that there used to be a "New File" button on the source page, but perhaps it was recently changed to "Add File" like you show in your post.
I figured I'd add to this just in case people in the future wonder about it.
Hey Community! We’re willing to wager that quite a few of you not only use Bitbucket, but administer it too. Our team is excited to share that we’ll be releasing improvements throughout this month of...
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