Dear Sajal, to be very clear there are no exam to enter in Data Science field. You need to gain experience in a particular field.

Now coming back to your question

Data science is the study of data. It involves developing methods of recording, storing, and analyzing data to effectively extract useful information. The goal of data science is to gain insights and knowledge from any type of data — both structured and unstructured.

There are three general steps to becoming a data scientist:

• Earn a bachelor's degree in IT, computer science, math, physics, or another related field;
• Earn a master's degree in data or related field;
• Gain experience in the field you intend to work in (ex: healthcare, physics, business).

There are many paths to landing a career in data science, but for all intents and purposes, it is completely impossible to launch a career in the field without a college education. You will, at the very least, need a four-year bachelor degree. Keep in mind, however, that 73% of the professionals working in the industry have a graduate degree and 38% have a PhD. If your goal is an advanced leadership position, you will have to earn either a master’s degree or doctorate degree.Some colleges offer data science degrees, which is an obvious choice. This degree will give you the necessary skills to process and analyze a complex set of data, and will involve lots of technical information related to statistics, computers, analysis techniques, and more.

All the best

Hope this helps