I want to know my phone is support esim or not

Read Apple's support document About eSIM on iPhone - Apple Support

This document says that eSIM is supported on: An iPhone XS, iPhone XS Max, iPhone XR, or later. This includes your iPhone 13 Pro Max

In this document Apple describes in the section How to set up an eSIM on iPhone the mechanics of setting up an eSIM, either when you first start the device or later.

Read also Find wireless carriers and worldwide service providers that offer eSIM service to find a carrier in your region which supports eSIM

A2644 (China mainland, Hong Kong, Macao),

No support for esim.

What is your model number?

Iphones meant for use in China do not support esim.