Once you have identified the correct GPIO number (e.g., 465), follow these steps to control it via the sysfs interface.

Make the GPIO accessible to user space:

$ echo 465 | sudo tee /sys/class/gpio/export

Configure the GPIO as either an input or an output:

# Set GPIO output
$ echo out | sudo tee /sys/class/gpio/gpio465/direction 
 
# Set GPIO input
$ echo in  | sudo tee /sys/class/gpio/gpio465/direction 

If configured as an output, you can set its logic level:

# Set GPIO output high
$ echo 1 | sudo tee /sys/class/gpio/gpio465/value 
 
# Set GPIO output low
$ echo 0 | sudo tee /sys/class/gpio/gpio465/value 

If configured as an input, read its current logic level:

$ cat /sys/class/gpio/gpio465/value

The command returns 0 (low) or 1 (high).

When finished, release the GPIO:

$ echo 465 | sudo tee /sys/class/gpio/unexport

If you encounter an error similar to the following when exporting, the GPIO pin is likely reserved for another function (e.g., by the device tree):

echo 465 | sudo tee /sys/class/gpio/export
tee: /sys/class/gpio/export: Invalid argument

Solution: Modify the Device Tree Overlay configuration to free the pin and define it as a standard GPIO.