Hey Souradeep!

SAT or Scholastic Aptitude Test is a standardised test given by students all across the globe to apply for various universities in the USA and other countries. The questions that are asked are from English and Math, until and unless you decide to appear for SAT subject tests, which asks questions solely from the subject you have opted for. Also, yes, it is a MCQ test. For more information regarding the SAT exam, it's pattern and the dates on which it shall be conducted and the venue, you are advised to visit the following links:

https://collegereadiness.collegeboard.org/sat/inside-the-test

https://collegereadiness.collegeboard.org/sat

Hope this helps. All the best!