I'm mid-iphone setup. I chose a wifi network but now I need to choose a different network in order to update my phone during setu

I started to setup my iphone not at home. I chose a wifi network around the apple store. I'm now mid-setup and the phone wants to update, but it's not updating. I'm not on wifi right now because I have since returned home... If I select "back" it takes me to options about pairing my watch and I can't go any further back... There's no other options on the phone right now... do I restart the phone?