As per your concern I will let you know details of Graduate Record Examination, so that you can check it and have idea.

The Graduate Record Examination is a standardized test that is an admissions requirement for most Graduate Schools in the United States that aims to measure verbal reasoning, quantitative reasoning, analytical writing, and critical thinking skills that have been acquired over a long period of learning

Eligibility
The only eligibility requirement for GRE is the document required to prove your identity. In India, you’ll need a valid passport.

You’ll have to get your original passport (not photocopies) which clearly shows your full name, photograph and signature.

No other documentation (like birth certificate, international driving license etc) can be used as an alternate identity proof. They are very strict about this.

Apart from this eligibility requirement, ETS does not set any age, qualification, timing related pre-requisites. However, there will be a range of eligibility criteria set by universities that accept GRE scores.

For each of their programs, they may have minimum age, experience and qualification related filters.

Exam Centres
Ahmedabad, Allahabad, Bangalore, Chennai, Cochin, Coimbatore, Dehradun, Gandhinagar, Gurgaon, Gwalior, Hyderabad, Indore, Kolkata, Mumbai, Nashik, New Delhi, Nizamabad, Patna, Pune, Trivandrum, Vadodara and Vijawada.

Exam pattern
The total duration of the GRE test is 3 hours 40 minutes.

There are six sections and a 10-minute break is given after the third section during the GRE test.

Measure Number of Questions
Analytical Writing(One section with two separately timed tasks) One "Analyse an Issue" task and one "Analyse an Argument" task

Verbal Reasoning (Two sections) 20 questions per section

Quantitative Reasoning (Two sections) 20 questions per section

Unscored Varies

Research Varies