To see the number of citations for a particular paper, open its ResearchGate page and check the number in parantheses after "Citations". But note that very often ResearchGate is not complete, i.e. did not find all citations.
Unfortunately, there is no possibility to sort papers by citations.
For a help page on citations, see https://help.researchgate.net/hc/en-us/articles/14293410769297-Citations.
As you are looking for number for citations fo some particular number of papers, just find an article, click the tittle and the new page will be opened regarding particular paper, which includes Research Interest Score,
Number of Citations, Number of Recommendations and Number of Reads.
Your total RG number of citations is 10.145, while h-index = 49.
For example, for this particular paper: Interaction of Colchicine-Site Ligands With the Blood Cell-Specific Isotype of β-Tubulin—Notable Affinity for Benzimidazoles, the number of citations is 2.
Article Interaction of Colchicine-Site Ligands With the Blood Cell-S...