At ResearchGate, you may upload your report as "unpublished research", but this will not be regarded as a publication. See this help page for instructions: https://help.researchgate.net/hc/en-us/articles/14293005132305-How-to-add-research. Note that ResearchGate is not a publisher and not a journal, therefore you cannot "publish" here. It is a platform for papers published in journals, or to present unpublished texts, data etc. See also "Is ResearchGate a publisher?" in https://help.researchgate.net/hc/en-us/articles/14292596164753. For a real publication, you have to look for a journal in your field of research and submit your paper there. See also the following discussions for recommendations:

https://www.researchgate.net/post/What_are_the_procedures_for_publishing_a_research_paper/1

https://www.researchgate.net/post/For_publishing_article_in_any_journal_which_necessary_steps_should_be_taken_care_by_a_new_researcher/1