Hi @Damien_Kelly- happy to help! It looks like you have already seen the community post Configuring OAuth 2.0 for Google services (Youtube, BigQuery, etc.) for authentication but just wanted to link it here as a reference for others who may see this post.
Once you’ve authenticated your Send to API step, you should then be able to use the BigQuery API documentation to set up that step to send over your information.
Are you running into any issues setting up that step? If it would be helpful, our team would be happy to take a look at your Flow to help troubleshoot. Feel free to send the name of your Flow and any error messages you are seeing to help@parabola.io and we can take a look!