If you're talking about uploading art, go to the top of your deviantART page where it says "Submit." Then choose "Submit Art" and choose the file you want to submit and the rest should be clear by then. Then you can upload that art.
If you're talking about uploading these deviantART Muro drawings you're making, those you can't upload as deviations. However, you could upload something from the deviantART Muro option found here:
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