Onboarding is where you set the name and details other people see in sessions. Nothing is pulled in from Google or anywhere else without you typing or confirming it - what you enter is exactly what members see.
You can also pick up to five emoji badges that sit next to your name - about 60 to choose from, in four groups: what I do, how I work, life and fun. You can skip any of it and do it later, and you can change all of it any time in Settings.