commerce course whose preparation I could start from 11

There are many courses which you can go for like CA, CS, BMS, BBS, ICWA after completing 12th. But this is the time when you need to make your basics strong because whatever course you choose after 12th will be requiring good basics so better to focus on 11th syllabus properly because this is going to help you alot in your bachelors.

Good Luck!!!