There are many IoT platforms out there, including Adafruit’s own Adafruit.IO, but if you want to build really big projects or run a business using IoT, you’ll need to use a platform that provides support for projects that scale. Microsoft Azure has resources for these types of applications and the best news is that you can use it with CircuitPython.
https://learn.adafruit.com/getting-started-with-microsoft-azure-and-circuitpython