Help. Newbie. Esim

I installed the eSIM and then it asked for the code, I swiped up to change screens to my email to get the code, but can’t get back to where to insert the code. 

Sim shows added to phone, but I have no service, how can I get back to give the PIN code that was emailed to activate the sim? 

thanks in advance 😊 

iPhone 16 Pro Max