To configure the software for intrastate billing, you need to set the invoice amount threshold for generating e-way bills.
Go to Administrator, then Configuration, then Features or Option, then select GST or VAT and enable the e-way bill required as Yes, then click on the configuration window and enter the necessary relevant details, such as the place, pin code, etc.and also Set the threshold amount for Central / Export Transaction and Local Transaction for the desired value for intrastate transactions.
This will ensure that e-way bills are generated for invoices above that threshold amount within the same state.