Actually there are, and always has been, some issues with Debian/Ubuntu and certain Broadcom wlan models.
If you can not get yours - after a regular installation - to run,
you are probably effected. Alas.
There are several ways to solve it, but after many investigations
from my side (because I was many times effected... [brmsmac]...)
I found that the most reliable way is
check your hardware installed by yourself - from the terminal:
$ lspci -nn -d 14e4:
Read the output well and find your model; eg:
03:00.0 Network controller : Broadcom Inc. and subsidiaries BCM43224 802.11a/b/g/n [14e4:4353] (rev 01)
or similar. In this example it is: BCM43224
With this knowledge you can find out now, which one is the right driver - here:
After you did identify your card with the correct driver in this list -
use synaptic to search and install the driver.
In the example above it is a bit more delicious, because
(reading the list reverse:)
BCM43224 = Driver: brcmfmac ; = Driver family: brcm80211
and ... "Non free firmware required": Yes
Means: Probably you will not find this particular driver with synaptic.
In this case the brcm80211 package needs to be installed (into the kernel):
$ apt install initramfs-tools
then jump to (here in this example I do need the driver for Debian Buster)
Debian -- Package Download Selection -- firmware-brcm80211_20190114-2_all.deb
choose a mirror from the list and download the file
install it (usually a double-click on the file is doing the job)
making sure all is well placed and working ; restart your machine.
For more extended how to's and other workouts you may like:
b43 and b43legacy:
Broadcom’s wireless LAN infrastructure portfolio: