In this section of the ultimate Power apps user guide I’ve included links to posts that talk about Flow integration.
Power Automate integration
https://sharepains.com/2020/06/22/power-automate-flow-powerapps-components/
https://sharepains.com/2019/11/08/renaming-flows-run-from-power-apps/
https://sharepains.com/2019/10/10/calling-long-running-flows-in-powerapps/