They’re all separate prompts. Number 5 asks for a photo of the bio page using the phone camera, and then number 6 asks to lay the phone (provided it has NFC capabilities) on the passport until it fully reads the biometric chip.

Step 7 opens the camera and takes a facial scan but not a photo. Number 8 is the next prompts that asks to take an actual photo.

This procedure can be done on a computer as well but I haven’t tried it that way nor do I know anyone who did though I’m sure number 6 doesn’t show up in this instance.

Some of these steps are skippable I can’t recall which ones but I also don’t know what the consequences for doing so are.

And you don’t have to carry your phone with you to verify your ETA. It’s linked to the passport and most of the time the check in agents and UK border staff will just see it there. Though in case someone asks for it you’d have to pull up your email as that’s the only place you’ll get proof. The valid ETA doesn’t show up in the ETA app itself and you can’t look it up otherwise as you would with ESTA, Canada and NZ and Australia’s ETAs.