Which are the top colleges to pursue integrated BBA and MBA course?

You can opt for integrated BBA + MBA course offered in various colleges. I think, IIM - Indore also provides this course. You can check the below mentioned link: https://www.shiksha.com/bba/articles/integrated-mba-programmes-in-india-blogId-15044

You can pursue BMS from DU. The fee structure is also very low. After completing BMS, you pursue MBA. In order to pursue MBA, you need to qualify entrance exams like CAT, MAT, CMAT,SNAP and NMAT.