Hello Soni!

IELTS has nothing to do with the fact that you passed from BBOSE board. Canadian universities refer educational agencies to convert your marks into their credit based system or traditional GPA system, so you have nothing to worry about that. Moreover, IELTS is an english-proficiency test, so it has least connected with which board you passed from. You can apply for universities anywhere in the world easily.

Canadian universities ask you to submit your transcripts including your academic records to the educational agencies that will convert your marks into the Canadian grade point system. In short, all the educational boards which are recognized by the Government of India will be valid for admission in any university, either in the country or abroad. Bihar Board of Open Schooling and Examination (BBOSE) is a recognised board, so the education from BBOSE will be recognized by Canadian Embassy to India as well.

Hope you are clear now!