What is the process to register my GSTIN and other details required for e-invoicing?

If you want to register your GSTIN for E-invoice you need to visit to the E-invoice portal and enable the E-invoice for your GSTIN 
To configure the E-invoice feature in BUSY follow these steps:
Step 1: Make sure that you have generated your GSP's/API credential on E-invoice portal such as Webtel and pinnacle.
Step 2:Now open your company in which you want to configure the e-invoice configuration.
Step 3:Now Click on Administration menu and click on configuration option
Step 4:Then click on Features and options button then click on GST VAT button.
Step 5:Now enable E-invoice required option selected as Y then click on GSP configuration button.
Step 6:Afterward select automatically to set GSP for both Eway bill and Einvoice.
Step 7:Then mention the user name and password for both GSP's in respective field and press ok button to save the configuration.
Step 8:Then Click on SAve button to save the changes on previous window.
Step 9: Then go to administration menu then click on configuration button
Step 10: Then open voucher series configuration and enable Input transport details and generate e-invoice after saving option and save it
Now go to transactions tab and open sale invoice and while generating E-invoice software will give you a prompt to generate E-invoice then you will be able to generate E-invoice directly from BUSY