To check if your device supports eSIM:
For iOS devices (iPhone XS and newer, iPad Pro, iPad Air 3rd gen and newer):
Go to Settings > Cellular/Mobile Data and look for "Add Cellular Plan" or "Add eSIM".
For Android devices:
Go to Settings > Network & Internet > Mobile network and look for "Add mobile plan" or "Download a SIM instead".
Most modern smartphones from 2018 onwards support eSIM.