eSIM is not exclusive to Apple, it is a technology that can be used by any eSIM compatible devices. However, Apple was one of the first companies to widely adopt eSIM in its devices, starting with the iPhone XR, XS, and XS Max in 2018.
Not all iPhones support eSIM, only the following models have eSIM support:
iPhone 14 Pro Max
iPhone 14 Pro
iPhone 14 Plus
iPhone 14
iPhone 13 Pro Max
iPhone 13 Pro
iPhone 13 mini
iPhone 13
iPhone 12 Pro Max
iPhone 12 Pro
iPhone 12 mini
iPhone 12
iPhone 11 Pro Max
iPhone 11 Pro
iPhone 11
iPhone XS
iPhone XS Max
iPhone XR
iPhone SE (2022)
iPhone SE (2020)
If you have an older iPhone model, it will have a physical SIM card slot and does not support eSIM. Note that eSIMs cannot be used on iPhones purchased from Mainland China. Most iPhone and iPad purchased from Hong Kong and Macao don't support eSIM except iPhone 13 mini, iPhone 12 mini, iPhone SE 2020, and iPhone XS support eSIMs.