Can I publish an artwork just for representing my portfolio, not for sale?

Can I publish an artwork just for representing my portfolio, not for sale?

Yes, absolutely! You can do it in the last step when uploading an artwork. In the section “Price & Availability” under “Artwork availability” choose the option “Not for sale”. This will also be indicated next to the artwork, so the artwork is visible for all platform users, but not available for sale.