build multi vendor ecommerce marketplace with pos

need to create a multi vendor ecommerce website with pos for single retials store and app. All indian GST complainces have to be maintained. marketplace website where admin products can be sold offline and invoiced with pos. item should have images, videos, attributes, hsn, tax local and out of state, multi category, serial numbers. Want to complete the project as soon as possible. All old data from old pos and website will have to migrtaed to the new one. The old invoices, purchase details, purchase invoice etc from old has to be migrated to new