How can we make the RFQ from Requisition?

Hi Experts,
We are new on sourcing that is why I am asking this basic question that how can we make the RFQ in sourcing from the Requisition made through i-procurement?  And after that how can we make the Quotation from them and make the Purchase order in core purchasing module?


Can any one share me the processes flow with navigation will be so much help full to me.


Thanks in advance