Slam another shot if you're playing the "where's the wifi firmware" drinking game.
Almost all USB and PCI wifi chipsets require proprietary firmware blobs be loaded by the driver into the hardware to work, and no doubt yours falls into this category. Per its commitment to open software, Debian does not ship non-free firmware with the standard ISOs, but make it available in a non-free section of the repository for easy installation, and there are also unofficial versions of the ISOs that include the firmware.
Anyway, we need to see the result of the lsusb command in a terminal in order to tell you what firmware package you need. If you have a wired connection, it can be installed by adding the non-free section of the repo, otherwise it can be downloaded on any connected machine and transferred to the Debian install for manual installation.
The MX Linux repositories
: Backports galore! If we don't have something, just ask and we'll try--we like challenges. New packages: Inkscape 0.92.1, Pale Moon 27.2.0, Liquorix kernel 4.9-18, mpv 0.24, Kodi 17.0, Shotwell 24.5, Mesa 13.0.6