Sim Card
Where can I buy a SIM card for the phone and does it already come with one in the phone
iPhone 13 Pro Max
Question marked as
Your SIM comes from - and belongs to - your wireless carrier.
Depending on how you purchased your phone, it may or may not already have one installed.
Also be aware that SIMs can be a “hard” (physical) nano-SIM OR a “soft” (programmed) eSIM.