what is the normal selection process of google?

You should maintain at least 65 percent marks throughout the academic career . It means 65% marks in 10th , 12th and B.Tech course .
2. There should be no backlogs when applying for Google Jobs .
All you need to appear for Google’s eligibility test is :
A Bachelor’s degree in Engineering with a good academic record .
Good knowledge in internet , web-search, online advertising , numerical analysis ,fraud detection and e-commerce .
Good written, verbal and interpersonal communication skills and ability to communicate clearly and efficiently .
There are various sections included in the test during test conduction . 
Questions from computer awareness
Verbal reasoning
Quantitative aptitude
Critical reasoning
And the standard of the questions depends upon the nature of the post .
The candidates who clear the written test are further called up for the interview .
Eligibility totally depends upon your performance in interview. Be very bold, confident and good communication. Your eligibility test will depend upon post you are applying for but a common process they follow is reasoning test(be very attentive during test), maths(basic things), aptitude (keep a eagle eye on every word of the question). Your academics of 60% and above will help you as well. Google always looks for passion, innovation and dedication. Be passionate and show your ability from the first round itself and this will eventually get u a job in Google. It is quite tough to crack Google's second round where you need to go for a online test time will be very less and questions are little tough ones. If you cracked this round the last Hr round will be totally easy just be calm and show them your skills and positive attitude and job is all yours.