Does the family sharing guardian gets notified when someone logs into my apple id?
If i logged into my apple id on a different device, would the family guardian be notified ?
I don't see why they would. However, signing into an account on a different device that you are only using temporarily is a very bad idea. Your account data and passwords might end up being shared with any accounts later signing into the device. Unless the device was erased first, you'd also find all kinds of unwanted data in your account. The exception is a computer where you have you have your own user area.
You don't say why you are asking this but one scenario is to try to share apps with a friend. This has other issues such as requiring a wait period before another account can sign into the device, plus a friend would not be able to update those apps.