My iPhone 13 not showing eSIM option

Most likely your iPhone 13 was manufactured for China, Macao, HongKong markets (where you cannot add eSIMs, just 2 physical SIMs).

Go to Settings>General>About and double tap on Model Number: you should see a code "Axxxx" (where xxxx are four numbers). Then check it here:

If it is a model 13: Model numbers: A2482 (United States), A2631 (Canada, Japan, Mexico, Saudi Arabia), A2634 (China mainland, Hong Kong, Macao), A2635 (Armenia, Belarus, Kazakhstan, Kyrgyzstan, Russia), A2633 (other countires and regions)

If it is a model 13PRO: Model numbers: A2483 (United States), A2636 (Canada, Japan, Mexico, Saudi Arabia), A2639 (China mainland, Hong Kong, Macao), A2640 (Armenia, Belarus, Kazakhstan, Kyrgyzstan, Russia), A2638 (other countries and regions)

If it is a model 13PROMAX: Model numbers: A2484 (United States), A2641 (Canada, Japan, Mexico, Saudi Arabia), A2644 (China mainland, Hong Kong, Macao), A2645 (Armenia, Belarus, Kazakhstan, Kyrgyzstan, Russia), A2643 (other countries and regions)

Regards

Giulio

Sorry no, no way to have eSIMs on that specific model (just 2 physical SIM cards).

Regards

Giulio