B.Com or BMS?
Either of them are fine.
BMS is for you if are determined to make a career in management and then later do MBA. It covers all the base subjects related to management, and hence could be your first step for a management career.
B.Com is a general degree, with major focus on accounting subjects and covers subjects like economics, HR etc., thus making it cover a wide range of subjects.
If you are not focussed or decided on management as a career yet, then B.com could be the best choice, provided you are comfortable with accounting subjects, as it is the major part of BCom curriculum.
BMS is focussed on management while B.com gives you a wide range of career choices, and in case later on, if you want to choose management, doing an MBA after Bcom is absolutely fine.
Weigh the pros and cons of each course and take your decision wisely.