Please Follow the steps shown below to create E-Invoice API id and password :

Step 1: Go to eInvoice official website and login into your account then click on API registration then click on Create API User

Step 2: Enter OTP received on your mobile number

Step 3:
– Select “Through GSP”
– On GSP list select “Charted information systems Private Limited”
– Create random username and password
– Click on “Submit” button

Step 4:
– Now you have to enter newly created username and password on Go GST Bill portal
Click on profile icon then click on “Settings” menu

Step 5: Now click on “E-way Bill & E-Invoice” option

Step 6: Enter “User ID” and “Password” that you have generated on step 3 then click on “Update” button