Need Help travel from Bangalore on May 17th AI 127

[Sankigatta]

My parents are traveling for first time in flight from Bangalore AI621 and then AI 127 from Bombay they will be leaving May 17 th early morning to Bombay and then to USA on AI127. They need help in understanding documentation in Chicago like immigration and customs and also going to domestic airport.

Any body traveling in same flight can help them.

Thanks,

Santhosh