GNU/Linux MX ALFA Network AWUS036ACH Wifi Adapter Driver Setup – Step-by-step Guide
The linked tutorial shows you step-by-step How to Install Alfa Network AWUS036ACH Wireless AC1200 USB Adapter Driver on MX GNU/Linux desktops – Step by step Tutorials.
And the MX ALFA Network AWUS036ACH Setup is based on the Realtek rtl8812AU Chipset Driver Installation.
So the linked guide explain How to Download and Install the rtl8812AU Linux Driver.
In case to check your Adapter Chipset see: How to Check Wireless Device ID on GNU/Linux.

GNU/Linux MX Installing Alfa Network AWUS036ACH Wireless Driver