Setup the default taxes for your business, you can still override defaults in the settings of individual products and services.
1. Go to Setup
2. Click on Tax
You can Enable or Disable Taxes when you required.
You can apply GST in the invoice which required these information like state, PAN, CGST, SGST, IGST etc.
Also set as Exclude or Include according to your need and Save
Also, here is the video tutorial for your reference