GNU/Linux Debian Bullseye Installing Broadcom BCM4312 Driver Guide
Hi! The linked Tutorial shows you Step-by-Step How to Install Broadcom BCM4312 Wi-fi/Bluetooth Driver in Debian Bullseye 11 GNU/Linux.
The Package Provides the Source Code for the wl Kernel Modules and makes use of the DKMS Build Utility to Install them for the Running Kernel.
GNU/Linux Debian 11 Broadcom BCM4312 Driver Installation Guide
Broadcom BCM4312 Driver Debian Bullseye Installation Guide