Hey Srijeev, Best places to visit with friends are :- Hampi Rishikesh Rajasthan Goa Varanasi Pondicherry Delhi Rann of Kutch Welll, as per me friends will make any place beautiful Bro ... Go Ahead with any one of these ... Happy Travelling !!!
7. Dudh Sagar
10. Ladakh bike trip
13. Uttarakhand trekking groups
14. Music festivals in different times of year
Triund trek in Himachal Pradesh is a fun short high altitude trek to go on with a group of friends. Manali and Shimla are fun to explore as well.
In Uttarakhand, Almora and Auli would be my recommendations.
While in South India, Vagamon in Kerala is a very picturesque hill station to spend a few days in.