How to transfer phone number from old iPhone 8 to new iPhone 12 Pro?

In the past I have just transferred the SIM card. But, this means that the SIM in my current iPhone 8 is most likely from an even older iPhone 5s. I have read that these older SIM cards are not fully compatible with the new 5G network of Verizon. I purchased the new iPhone with a Verizon SIM from the Apple online store. How do I transfer my phone number from the 8 to the 12? Does this require a call to Verizon?

If so, should I call Verizon and do the phone number transfer first, or should I transfer data from my old iPhone to the new one before having the number ported? Or does it even matter as to the order? Thanks!