How do you call people in other countries?

Im trying to call a friend who lives in india. im in the united states. how do i call them? i know that you have to dial 011 and then what country and then area code and then their number but when i tried it (i tried calling my home phone from my cell phone to make sure it worked)and it looked like this 011-151-5xxxxxx. all the websites ive looked this up on said it should look like 011-1-515-xxx-xxxx. what am i doing wrong?How do you call people in other countries?
Your suppose to get a phone card. That's how I've called in the pastHow do you call people in other countries?
011 + 91 + area code + phone number. I calling a cell phone, it's 011 + 91 + 9 + Number



The area codes are between 2 and 4 digits. 515 is Unnao.