Yes I got the warning about being rooted too. I think the app is mistaken since as far as I know /e/ does not root devices, but then I am a noob too so what do I know.
The Aurora store carries everything in Google Play store. Whether the apps work or not is another matter.
Aurora logs into Google Play with an anonymous account to do the downloads. If you have an app in Google Play you have previously paid for you can log into Aurora with your Google account settings to retrieve it. Do not forget to log out again afterwards or else you will remain logged into Google Play.
Many apps in Google Play/Aurora contain trackers, so where possible try to find suitable apps either in the /e/ App store, or in the F-droid store. F-droid contains only open source apps.