A: Use business process flows to define a set of steps for people to follow to take them to a desired outcome.
These steps provide a visual indicator that tells people where they are in the business process.
B: Push notifications are used in Power Apps mobile to engage app users and help them prioritize key tasks.
In Power Apps, you can create notifications for Power Apps mobile by using the Power Apps Notification connector. You can send notifications to any app that you create in Power Apps.
E: Create a cloud flow when you want your automation to be triggered either automatically, instantly, or via a schedule.
Automated flows: Create an automation that is triggered by an event such as arrival of an email from a specific person, or a mention of your company in social media.

Reference:
https://docs.microsoft.com/en-us/power-automate/business-process-flows-overview
https://docs.microsoft.com/en-us/powerapps/mobile/power-apps-mobile-notification