Help change from google drive to gsuite & migrate 4 emails from zoho to gmail business

Hi I am trying to switch to google drive (from dropbox business) to save money As well as zoho mail to gmail (for my business). I have now uploaded all our files to google drive and am trying to upgrade to gsuite, however can't figure out how to do this using my work email (as I have already created a google drive account using my work email). I need a google expert to: 1. help me set up gsuite basic plan for our 4 work emails 2. and also setup our gmail for our 4 work emails and 3. import all sent & received emails (in their folders) for our current emails (currently in zoho mail)