
First of all what is a port ?
a port in networking is a software-defined number associated to a network protocol that receives or transmits communication for a specific service
netstat stands for Network statistics its a Unix-like operating system command, netstat is a command-line network utility that displays network connections for Transmission Control Protocol (TCP), routing tables, and a number of network interface and protocol statistics
if netstat is not installed by default on your OS here’s how to install it in different Linux OS:
On Debian/Ubuntu & Mint :
sudo apt-get install net-tools
On CentOS/RHEL/Fedora and Rocky Linux/AlmaLinux :
sudo dnf install net-tools
On Arch Linux :
pacman -S netstat-nat
On Gentoo
emerge sys-apps/net-tools
On OpenSUSE
sudo zypper install net-tools
Once you finish the installation, you can use the netstat with grep command with pipeline between them to find the process or the service listening on a particular port in Linux
netstat -ltnp | grep -w ‘:[PORT]’
for exemple lets try the port 80 :
netstat -ltnp | grep -w ‘:80’

In this command we used options :
l – tells netstat to only show listening sockets
t – tells netstat to only display TCP connections
n – tells it to show numerical addresses
p – to show the process ID and the process name
grep -w – shows matching of exact string (:80)
And Thats it! , if you know any other ways to finding service or process listening on a particular port, let us know by a comment from below.