Hi Shalini
The question as to whether something is easy of not would entirely depend on your aptitude, interests and skills.
What is your general background within your education/degree. I think you need to take the time to learn more about your skills before you jump into the next training course.
What have you researched about SAP BI? Have you looked at some of the free online courses (including SAP Learning Hub Discovery Edition) to get a better understanding? Also, you could have a look at help.sap.com for some basic overview.
In relation to institutes, have a looked at SAP Education site for your country and they will have a list of authorised training providers
Regards
Colleen