Step 1:
Copy & paste or type the following command into Terminal to make sure your version of KaliPi is up to date.

sudo apt update && sudo apt upgrade

Make sure to reboot after all updates are complete.

Step 2:
Copy & paste or type the following commands one line at a time into Terminal.

sudo apt install -y kalipi-kernel-headers build-essential bc dkms git
mkdir -p ~/src
cd ~/src
git clone https://github.com/morrownr/8821au-20210708.git
cd ~/src/8821au-20210708
sudo ./install-driver.sh

How to Remove the Driver:
Copy & paste or type the following commands into Terminal.

cd ~/src/8821au-20210708
sudo ./remove-driver.sh

The GitHub author welcomes suggestions and pull requests.