Can I submit files to the API that are stored in a Google Drive?

Yes, you can but the file needs to be shared publicly, smaller than 100MB, and the URL needs to be a downloadable link, which should look something like this:

https://drive.google.com/u/0/uc?id=1OMjFJ1VUX0ES5tMSdslybvPLxYTjdqLZ&export=download

See this guide from our AssemblyAI Cookbooks for a detailed walkthrough of how to submit files from Google Drive.