ifconfig
Make a note of your IP address. It should be
172.16.1.203
nmap 172.16.1.203
When the scan completes, you should see a list of open ports including
"80/tcp", as shown below.
Kali includes the iptables firewall, which is very powerful, but difficult to use.
However, for this project, we'll use "ufw" -- the Uncomplicated Firewall.
In your Kali32 machine, in a Terminal window, execute these commands:
ufw enable
ufw status verbose
As shown below, this firewall
allows all outgoing connections,
but blocks all incoming connections.
This makes your Kali32 machine a client, but never a server, which is the same thing the Windows firewall does by default on public networks.
nmap 172.16.1.203
The scan is much slower now. When the scan completes, you see
"All 1000 scanned ports ... are filtered",
as shown below.