How can I see how many conversations have been started/closed/reopened by a teammate?

Hey @user1375​ ! Oséas here from the Customer Support Specialist team 🕵️

The best place to get stats like these is under your Teammate Performance Report. It'll give you a table with your teammates' main stats 👇 

However, it won't give you data for reopens or initial source. If you want more detailed stats the best way of getting it would be by exporting conversation data as a CSV file and then opening this file on a spreadsheet software such as Google Sheets. You can find more details about this export here.