Suggest Uncrowded Scenic (Lake, River with Green cover) For A Outing

Hi everyone. I'm visiting Guwahati for a week. I'm originally from Assam, but have not lived here for long. I'm planning to take my car and go for a long drive in some scenic route. I dont want to go to the Shillong route. Can you please suggest some place/route? Also, kindly suggest Eco camps where I can possibly spend the night in a budget. I will mostly be alone and at most my elder sisiter might join me. I want to avoid crowded, lound and dirty places. I take cleanliness and peace of mind quite seriosuly. Thank you so much!