Hi, Indeed, admission to courses like BSc Economics at MIT-WPU (MIT World Peace University), Pune, typically requires passing an entrance exam. The exam often evaluates your expertise in economics as well as fundamental areas including general knowledge, maths, and logic. It is an aspect of their admissions process, and students must normally take the test in order to be considered for admission.
Regarding your PCMB, there shouldn't be any major problems with pursuing a BSc in Economics if you have a strong background in science (physics, chemistry, mathematics, or biology). Even though economics is typically thought of as a social science-based study, many universities, including MIT-WPU, welcome students from a variety of backgrounds. Since quantitative analysis, statistics, and problem-solving are frequently used in economics, your mathematical expertise from the PCMB stream may really work to your benefit.
I hope this is helpful!