What is difference between SSB, CDSE and AFCAT?

My cousin qualified for the AFCAT (Air Force Common Admission Test) exam in 2018 into the AFSB which is an acronym for Air Force candidates. Basically, it is just the first step, including the CDSE which is the short form of the Combined Defence Service Exam. So these exams work as a filter in letting the best candidates come to the surface, these then go to the SSB/AFSB. 

Here are some key points on the process-

• Candidates who join the army or navy are termed 'SSB', and those who join the Air Force are called 'AFSB'.
• AFCAT is the exam by and for the Air force when there is a requirement of staff for general duty, technical, flying, logistics, or administration. It is conducted bi-annually in the months of March and August and is the only other mode of entry into the Air force apart from CDSE.
• The process remains the same for all these agencies during the first few days. After clearing the first step, your scores are sent to the headquarters and you'll have to qualify for the PABT test, in case you've chosen the flying branch. Alternatively, you'd have to qualify for a basic knowledge test for the groundwork.
• If you qualify and reach SSB (Service Selection Board), you'll be a participant in another filtration process of which only 80 out of 300 candidates will be selected.

If you wish to become an officer in the three defense forces, you'd have to submit a clearance by SSB or AFSB. If you're selected through the CDSE and NDA, then you'll be given the Permanent commission (PC) and if you have qualified AFCAT, then you'll get selected for Short Service Commission (SSC). Although, sometimes technical and non-technical staff go through the AFCAT only (not through CDSE) and they get through PC.

Note that if you fail PABT, your flying dreams are over, as far as IAF is concerned. So be careful there, you'll need a lot of patience and resilience to go through the process.