How can I make phone call from my iPad

As everyone has pointed out, WiFi and cellular DATA iPads do not make cellular phone calls on their own.

Sorry.

To use an iPad to make cellular phone calls and to send SMS text messages, you need to have a iPhone that the iPad is tethered to that acts a remote call and SMS text messaging device linked to an iPhone.

Check this link...

Make and receive calls on your Mac, iPad, or iPod touch - Apple Support

Note that you cannot make a call from an iPad just because it is a cellular device with a SIM card. You can make a call from an iPad if you have an iPhone as described in the kb article that frazzm737 posted for you.