Come to Canada and then get him over here. We have an open door to people from India. Just land your plane at Vancouver International Airport and you will think you were in Bombay by the looks of the people you first see.How can my parent's call my little cousin from India to come here for school?
Students who come to the US are supposed to come on an F-1 visa. A student can attend a private elementary or secondary school. The law also says that students can attend a US public high school but must reimburse the school for the full amount of tuition. The school district should be able to tell you what that is, but it could be around $10,000/year. The school district may also have custody/guardianship requirements that need to be complied with.
Once you identify the school your cousin wants to attend, he will need a SEVIS Form I-20 (DS-20) to apply for the F-1 visa. The SEVIS form certifies the school exists, that he has been admitted, and how the fees will be taken care of. With that, he applies for the F-1 visa at the US consulate.
Go see the people that handle immigrations.