Hello,

In order to become microbiologist you will have to choose microbiology as your subject in the final year of your Bsc. And just Bsc degree is not enough if you want to go in the research field or want to do something in microbiology. You need to do Msc and for that you can give exams like JAM or KVPY to get best colleges so that you have research environment. Some people also go for  Phd. Make sure you are also performing some research in your domain and all the best to you. Check out below link

https://university.careers360.com/colleges/list-of-microbiology-and-virology-universities-in-india