How to scan open TCP/UDP ports of Host with Zenmap (Nmap)

Follow the steps:

• First download Zenmap gui (nmap for windows).
•  Install and open zenmap on windows.
• Fill target host(which you want to scan).
• Select scan type (Intense scan , regular, ping scan, trace rout, udp scan etc.).
• Hit scan.
• Wait for a minute till scan is not completed.(see screenshot below) 

Thats it.Scanning Done.

Note: First connect your PC to a network (wi-fi).If you are using modem then scanning can't be perform due to restriction on windows.(Error shows you can not scan your own machine i.e Localhost).
For scanning your own machine use --unprivileged command.