Want to close sole propritorship

I want to close my father's company, it is sole proprietorship company. All banks account and vat and gst registrations is on his name but due to his bad health condition, he is not able to sign and carry on business, so till now i'm handling the business but now i'm facing difficulties with banks, so i want to close the firm and want to open new company in my name. So please tell me the procedure to close the business and cancel the VAT and GST Registerations.