How do you see restricted numbers on the google phone?

I keep on getting restricted numbers and I wanna know who it is, so yeah please help me. and by the way, not trapcall, not anything I have to pay for, and not going to the police or anything like that. and yeah I have a google phone. g1|||No other way besides using trapcall or Kall8. Kall8 requires you to pay,but it is a cheap price.