1. The Partnership firm would have to be dissolved through drafting of a dissolution deed. The assets/goodwill/capital remains with you, and the erstwhile partners would be reimbursed for the same. You may also impose reasonable restrictions on them to restrain them from interfering with the carrying on of business in future.
2. To start sole proprietorship you require the PAN card, Current Bank Account in the name of the business you want to do to be operated by you as Proprietor & Registration with the Government Department where the trading business you want to do is required. In case this being service providing business the registration for service tax with revenue department will be required, similarly if this will be with regard to sale of goods the registration for the VAT will be required with the local State government. If it is being operated from a shop or commercial place then registration for the Shop & commercial establishment will be required with the local state government. No such written deed is necessary for the Sole Proprietorship Business. However if any of the Government Department where the Registration of the business is required seek a written deed of the proprietorship business then one can reduce all the details with regard to the identity of the owner, the nature of business to be carried out, financial, property & other Capital the sole owner contributed, the details of bank accounts to be maintained for the business, the full details of loans or any financial advances taken for the establishment of the business, property mortgaged for this purpose & mode of repayment, nature of accounting, details of the books to be maintained for the accounts, the person/s who will be beneficiary in event of death of the sole owner etc.