Yeah even the setup is as easy as plugging it into a browser and pressing some buttons but booting the phone into recovery and wiping it to install a custom OS is always gonna be daunting to most people even if it's automated tbh.

For the sandboxed Google Play Services just open "Apps" (the Graphene one with the white logo) and you can install the Play Store from there. It'll install all the rest of the dependencies at the same time. Once it's done, open the Play Store even if you don't wanna login just yet just so it's been opened at least once. After that you got the barebones Google Play Services sandboxed like regular third party Android apps.

You can install more Google and third party apps either from the Play Store or the Aurora Store.