Useful computer courses for B.Sc in IT and B.Com (//B.Com) students are:-

In marketing field:

* Web Designing, Graphics Designing, UI or UX Front End Developer

* SEO, Search Engine Marketing, Digital Web Marketing

* AutoCAD, Photoshop

In finance field:

* Microsoft suite

* Macro and C++,  Java

* Bloomberg and Reuters

* SAP

* SQL

In Operations:

* Software Test Engineer or QA Engineer or Quality Assurance

* JETKING (Hardware) or NIIT or ICA (Accounts related)

Hope this information helps you.

Wishing you a good luck!