Our company has made a form with Typeform. Is it possible to trigger the onSubmit event when a new response is sent to the spreadsheet from the Typeform form? Or is there some other way to detect new responses in the spreadsheet?
Is it possible to trigger the onSubmit event when a new response is sent to the spreadsheet from the Typeform form?
You can't do that. Google Forms and Typeform are two different platforms with different mechanisms. The onSubmit event of a google form cannot be made to work with Typeform.
You can write a script to 'poll' the Typeform API (as others have suggested) but there is a more efficient way to achieve what you require.
You'll need to leverage Typeform's Webhook API in tandem with a webhook endpoint. You can deploy a stand-alone apps script as a web app and use it's URL as an endpoint for webhook payloads. The script can then be made to process Typeform submission data and place it into a Google Sheet.