Dear Friend,
I think there is no provision that talks about conversion of Sole Proprietorship into Pvt Company.
The Section 366 of CA 2013, says any company/entity that is registered under any law can be registered under this section and the Sole Proprietorship is not an entity registered under any law.
The normal practice and better process for your requirement is:
1. Form a Private Limited Company
2. obtain valuation for Sole Proprietorship Assets & Liabilities, if such a big entity
3. Acquire that Sole Proprietorship
4. if you want to issue/allot shares then allot for kind