How to raise an alarm from a GPIO pin of Jetson Nano once an object is detected?

hello farjadhaider3253,

suppose there’s an software events once an object is detected,

you may refer to Jetson GPIO, it’s a Python library that enables the use of GPIOs. please check the sample python scripts, i.e. button_event.py for reference;
or, you may refer to Jetson-Nano GPIO example to directly read/write through /dev/mem

please also check similar discussion thread, Topic 144550 for reference.
thanks