Get back to the main city and have some good food to deal with your hunger at lunch
Buddhism is the main religion of the most indigenous people of Bangladesh. So, get on your vehicle to head towards the Buddhist temple and explore Buddhism with the followers
Visit an amazing Buddhist temple over there with one Buddha Statue, prayer hall etc.
Learn about Buddha, his principles from his followers and make a pray with them
Take a short boat ride to get on the Old Rajbari (Kings Palace) of Rangamati
Start for a tribal market where people come with their own produced crops, handicrafts and many more..!!!
Visit the tribal market, do some shopping if you like, talk with them and get an interactive session with them on their lifestyle and history..!!
Have some snacks with some fresh fruit juice at a cool hangout place with a wide view of Kaptai Lake
Take a music lesson from some indigenous people and learn their stories that they kept telling years after years through some awesome music