Hello,

Yes,you can take admission in 11th class with whatever stream you want if your school is allowed to do so. actually registration for class 12th board is done in class 11th which may hurdle you if registration is completed for 12th in your school then it is not possible to change stream.

Get more information in the link

https://school.careers360.com/exams/west-bengal-12th

Hope it helps..