If I buy an iPad will i be able to call someone with an ipad just like an iphone?

No. No calls.

But if you have wifi you can video call (face time)

But no, you can't make normal calls with an iPad that would be ridiculous, imagine holding a 10 inch board to your face while driving or walking down the street. Lol.

You could download an app on an ipad to call people for free around the world, but you can not call people with an ipad without an app. An ipad is not really different from an iphone but all you need to do is download an app, for example magicjack is really good to make free calls around the world.

No you can't call someone with an apple ipad unless its a video calling service like facetime or skype

iPad doesn't have the option to call just ask Siri but you can make a skype or FaceTime call

You could call using FaceTime Audio or Video Chat or video conferencing apps but no you cannot use service from like ATT to call people.

You can chat with app like whatsapp or use Facetime. Obviously its not a phone.

if you are on wifi and use skype or text free you can make calls