If he is in class 11th then it is approximately a right time to make up mind and start taking subjects like PCM seriously.
I personally know that askIITians is providing coaching in Qutar and many of the students are already there with them from Qutar and preparing for engineering examinations.
You can view the complete course progrma for IIT JEE here. IIT JEE Classroom Program
Yes askIITians do provide online coaching for the students.
IIT - Mumbai