If you are planning a foreign trip under budget, then you could go to Bali or Thailand. If. In India, then north or north east are the best destinations.
Kashmir, leh, Shillong, Meghalaya, sikkim, Dharamshala, dalhousie, Gangtok, Darjeeling, tawang.
Shimla, kullu, manali, on the north. there are several offbeat places in himachal pradesh. in the east, Darjeeling, Gangtok, yuksam, ravangla, pelling, Shillong, etc. you can also try munnar in the south
If you're looking at an international location, you can try Eastern Europe. We were in Budapest & Prague for a short while this summer and it felt magical. These are not very expensive places and make perfect locations for honeymooning. You can read up about it here - https://www.tripoto.com/trip/best-of-budapest-in-12-hours-5d832c527dd70