Before it was possible to manually add citations to ones publications on RG, but this function has been discontinued as RG improved the automatic search for citing papers. Now both platforms only add citations automatically.
The only thing one can do on the platforms is to make sure all ones publications are listed.
There is a loophole on RG that seems still to be open. If you upload a .pdf of your paper which quotes any of your previous works that might be missing citations to it seems the RG platform scans the .pdf and add the citation.
The platform revolves around research papers, a question and answering system, and a job board. ... One of the focal points in ResearchGate's e-mails is a researcher's latest ResearchGate Score (RG Score). Updated weekly, the RG Score is a single number that is attached to a researcher's profile.