Hello @YOUANDME
Thanks for reaching out to our Nest Community about this fan funtion on your Nest thermostat. I apologize for all the inconvenience. I'm here to help you with that.
To answer your question, yes you can turn on the the fan without turning on another function. However your system needs to have a ¨ G ¨ wire connected on the base to your Nest Thermostat to perform this action.
You can learn more about Fan control with a Nest thermostat here.
Feel free to keep us posting if you have more questions about your device.
Best regards,
Douglas.
