What are the options for transporting goods with an e-way bill using different modes? How do I update the details if so?

Yes. You can transport goods via different modes of transportation: Road, Rail and Air. However, PART B of the e-way bill must be updated with the most recent mode of transport or conveyance number by using the Portal's 'Update vehicle number/mode de transport' option. This means that at any time, the 16 details about conveyance in the portal's e-way bill should match the details of the conveyance through which the goods are actually being transported.