There are various courses available,it completely depends on your own choice which course you want to choose .As you are a commerce graduate you can choose courses like M.com,CA,CS,CWA,CMA,CFA,etc.

Other options available are MBA,Law,diploma courses,etc.

Best of luck

Hi,
As far as MBA is concerned, it is highly preferable course after doing B.Com.
Most of the students prefer to join MBA after successfully completing graduation in commerce. If you want to study further, you can go for MBA, M Com, Chartered Accountancy or Cost Accountancy careers which are equally attractive.
The following are the fields which can be opted in MBA .

1. MBA in Finance
2. MBA in Marketing
3. MBA in Human Resource
4. MBA in Banking

You can even choose dual specialisation in MBA Finance/Marketing so as to make the best use of the available job opportunites as dual specialisation helps to gather the basics of both the fields.
You can apply for CAT and XAT as the applications have already started.

CAT Application Form
XAT Application Form

You can even consider the below:

• Company Secretaryship - where you get involved into a company's administration. Secretary positions are reputed within a company especially in education and manufacturing industries. It requires you to be further qualified for professional secretarial examinations. But the basic degree that it demands is a BCom degree. Duration: Complete 3 years article ship and GMCS (15 days).
• Chartered Accountant - this requires you to study for a professional qualification like the CA. As a chartered accountant, you have high job prospects in India and abroad. Chartered accountants are always in demand with the BIG Four companies like the Ernst & Young, Deloitte, KPMG and PWC. If you aspire to work for the BIG Four companies, you can also start on an entry level role with a BCom degree. And you may simultaneously prepare for your professional exam while you are working. Duration: Complete 3 years article ship and GMCS (15 days).
• You can even pursue ICWA that is Institute of Cost and Work Accountant. The duration is:

Entire course consists of three stages foundation, intermediate and final.

1. Foundation: Minimum duration-8months.
2. Intermediate: Minimum duration-10 months.
3. Final: Minimum duration-18 months. Hope this helps.

Good luck!!