GNU/Linux Alfa Network AWUS036ACM Setup – Step-by-step Guide
Hi! The linked Tutorial shows you Step-by-Step How to Install Alfa Network AWUS036ACM Wireless 802.11ac Driver in GNU/Linux Computers.
And the Linux Alfa Network AWUS036ACM Adapter make use of a MediaTek MT7612U Chipset.
Especially relevant: this Driver is supplied from Linux 4.19 but some important Connection Issues has been fixed only starting from the 5.4.1 Kernel release.
And in Debian-based it may be just missing the Proprietary Firmware!
GNU/Linux Alfa Network AWUS036ACM Wireless Driver Installation Guide