I have also tried installing another driver by:
sudo apt-get update
sudo apt-get purge bcmwl-kernel-source
sudo apt-get install firmware-b43-installer
I got this error message in the output because the checksums didn't match
colin@colin-MacBookAir:~$ sudo apt-get update
[sudo] password for colin:
Ign:1 https://mirrors.ocf.berkeley.edu/linuxmint-packages xia InRelease
Hit:2 http://mirrors.ocf.berkeley.edu/ubuntu noble InRelease
Hit:3 http://security.ubuntu.com/ubuntu noble-security InRelease
Hit:4 http://mirrors.ocf.berkeley.edu/ubuntu noble-updates InRelease
Hit:5 https://mirrors.ocf.berkeley.edu/linuxmint-packages xia Release
Hit:7 https://repo.protonvpn.com/debian stable InRelease
Ign:8 https://packages.microsoft.com/repos/code stable InRelease
Hit:9 http://mirrors.ocf.berkeley.edu/ubuntu noble-backports InRelease
Hit:8 https://packages.microsoft.com/repos/code stable InRelease
Reading package lists... Done
colin@colin-MacBookAir:~$ sudo apt-get purge bcmwl-kernel-source
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following packages will be REMOVED:
bcmwl-kernel-source*
0 upgraded, 0 newly installed, 1 to remove and 1 not upgraded.
After this operation, 22.5 kB disk space will be freed.
Do you want to continue? [Y/n] Y
(Reading database ... 554388 files and directories currently installed.)
Removing bcmwl-kernel-source (6.30.223.271+bdcom-23ubuntu1.1) ...
colin@colin-MacBookAir:~$ sudo apt-get install firmware-b43-installer
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
The following additional packages will be installed:
b43-fwcutter
The following NEW packages will be installed:
b43-fwcutter firmware-b43-installer
0 upgraded, 2 newly installed, 0 to remove and 1 not upgraded.
Need to get 0 B/33.0 kB of archives.
After this operation, 126 kB of additional disk space will be used.
Do you want to continue? [Y/n] Y
Preconfiguring packages ...
Selecting previously unselected package b43-fwcutter.
(Reading database ... 554385 files and directories currently installed.)
Preparing to unpack .../b43-fwcutter_1%3a019-11build1_amd64.deb ...
Unpacking b43-fwcutter (1:019-11build1) ...
Selecting previously unselected package firmware-b43-installer.
Preparing to unpack .../firmware-b43-installer_1%3a019-11build1_all.deb ...
Unpacking firmware-b43-installer (1:019-11build1) ...
Setting up b43-fwcutter (1:019-11build1) ...
Setting up firmware-b43-installer (1:019-11build1) ...
No chroot environment found. Starting normal installation
No supported device found.
But firmware is installed unconditionally
Unsupported device(s) found: PCI id * 14e4:43a0
Unknown device(s) found: PCI id * 14e4:43a0
Trying to install latest firmware 6.30.163.46 .
--2025-07-21 11:08:36-- https://www.lwfinger.com/b43-firmware/broadcom-wl-6.30.163.46.tar.bz2
Resolving www.lwfinger.com (www.lwfinger.com)... 15.197.172.60
Connecting to www.lwfinger.com (www.lwfinger.com)|15.197.172.60|:443... connected.
HTTP request sent, awaiting response... 200 OK
Length: 114 [text/html]
Saving to: ‘broadcom-wl-6.30.163.46.tar.bz2’
broadcom-wl-6.30.163.46.tar.bz2 100%[=====================================================================================>] 114 --.-KB/s in 0s
2025-07-21 11:08:37 (15.1 MB/s) - ‘broadcom-wl-6.30.163.46.tar.bz2’ saved [114/114]
broadcom-wl-6.30.163.46.tar.bz2: FAILED
sha512sum: WARNING: 1 computed checksum did NOT match
/var/lib/dpkg/info/firmware-b43-installer.postinst: Downloaded firmware did not match known SHA512 checksum, aborting.
dpkg: error processing package firmware-b43-installer (--configure):
installed firmware-b43-installer package post-installation script subprocess returned error exit status 1
Processing triggers for man-db (2.12.0-4build2) ...
Errors were encountered while processing:
firmware-b43-installer
E: Sub-process /usr/bin/dpkg returned an error code (1)