You can use Dual SIM with the following: iPhone XR, iPhone XS, iPhone 11, iPhone 12, iPhone 13, iPhone SE (3rd generation), and iPhone 14 (purchased outside the U.S.); these models can use one physical SIM and one eSIM. iPhone 13, iPhone SE (3rd generation), and later; these models can use two eSIMs.
not sure how it works on the watch though