is device id in android phones unique or changeable

Hi i am new to android. i am confused if device id in android phones is unique to the phone or associated to the google play account or changeable.

the reason i ask this is because i want to use a software called apk leecher to download apps as i currently dont have wifi with my internet connection and apk leecher asks for device id of the phone and i am worried if its risky.

thanks in advance