Anywhere within your state ,within your reach. collect all the information about the places you cud stay ,eat , explore, weather, transportation,and community around .. then plan accordingly. you didn't mention where do u live so here are some options u can consider them if you live somewhere around these places.
Dharamshala masoorrie Goa
Again this depends on your liking ( hills vs beaches vs historic place) , time of the year and budget. E.g. I went for my first solo trip to Cambodia in Dec 2018 You may pls go through my published blog for the details of the trip.
It depends on your liking if you are doing 1st solo trip then try to choose destinations with live events.. destination really doesn't matters but the experience is so choose it wisely and according to what kind of experience you want from that trip
If someone really interested for its 1st solo trip then there are many places in India and in the state Odisha too. Places like Puri, Konark and other places one can visit. During the visit one can search many hotels in Bhubaneswar The HHI Bhubaneswar is one of them. Which provides better facilities at a very affordable price.