Please note that ResearchGate is not a publisher, you cannot publish a paper here. It is a platform for papers published in journals, or to present unpublished texts, data etc. See these instructions how to add published or unpublished reasearch: https://explore.researchgate.net/display/support/How+to+add+research

Because research gate is not a publisher, you cannot publish an article on ResearchGate. Its a forum for researchers or the people having research interest. Journal papers can be presented on research gate, together with previously unpublished works, statistics, etc. However, In a trial project, Wiley and ResearchGate will make Wiley journal articles accessible on ResearchGate. Check out these rules Adding research, whether it is published or not: how to do it:

https://explore.researchgate.net/display/support/ResearchGate+and+Wiley+partnership

Hope this is useful.