iPhone X , available for esim ?

Unfortunately no, you can’t.

The Xs and XR models were the earliest iPhones to support eSIM.

See “What you need” in this article:

Using Dual SIM with an eSIM - Apple Support

iPhone 13 was the first concerted “push” of eSIM.

The US iPhone 13 ordered from Apple could automatically provision from your designated carrier OTA as soon as they were “removed from their box” and 1st turned on.

It’s certainly the “way of the future.”