See for most of the bank you need to clear competitive examination. Thus there are no such limitations regarding the UG course to do a job in bank. You can pursue any course of your choice which is a UG degree course then you are eligible for a job in bank. Thus what you have to do is that you have to prepare for Bank examinations along with your UG syllabus. As you have mentioned you are a commerce student then I would say go for BCOM general.
I mentioned here BCOM general because you need to practice and study a lot for Bank examination. If you go for BCOM Hons then you will get very less time to study but in BCOM general you will have less pressure and you can give more time to your Bank examination than your BCOM.
Some of the most preferred bank examination are:
To know more about this examination visit the link below:
https://competition.careers360.com/articles/sbi-po
https://competition.careers360.com/articles/sbi-clerk
https://competition.careers360.com/articles/ibps-po
https://competition.careers360.com/articles/ibps-clerk
I hope this answer helps. All the very best for your future endeavors!
Investment Banker Eligibility
Banker (RBI) Eligibility
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