Dear Jigyasa, until you reach the counselling phase and you are joining any college, you don't need any original certificates. You can upload a copy of your educational documents. You haven't mentioned what you are studying in private college but ideally you can request the Authorities for certificates for counselling purposes and no adminstration can deny you your certificates. Once you get a seat, you can apply for TC and join the new college you get in CLAT counselling.