Should I enable e-waybill integration in BUSY settings?

Yes, you should enable E way bill feature in BUSY if you want to generate e way bills directly from the software.
To enable the E Way Bill feature in BUSY follow the below steps:
Step 1: Open BUSY and go to Administration.
Step 2: Click on Configuration and then select Features/Option.
Step 3: Click on GST/VAT tab.
Step 4: Enable E way bill required feature then click on configure and specify your place and pin code, you can also mention amount after which eway bill is to be generated for local as well as central transactions with user restrictions also.
Step 5: Click on GSP Configuration and enter Webtel Electrosoft Private Limited and Pinnacle Finserv Advisors Private Limited User id and password which is created from eway bill portal and save the configuration.
Step 6: Go back to Administration and click on configuration.
Step 7: Choose the Voucher Series Configuration option and select the voucher type for which you want to generate e-way, such as sales, sales return, etc.
Step 8: Then, select the voucher series and click on Voucher Configuration.
Step 9: Here, you will see options of Input Transport Details, Generate E way bill After Saving, set Y to enable that. 
Step 10: Now when create invoice can generate automatic e way bill.