Is there any way to use a normal GPIO pin as a 5V output pin? I am using a screen that prevent access to all power outputs, so I have only the normal GPIO pins and ground pins, not mentioning the id_sc and id_sd pins. Also what do they do?
GPIO are not meant to supply much power. I believe the limit is 20 ma at 3.3v on the Pi. This isn't just for the Pi, but every microcontroller and microcomputer chips I've known about (other chips may have different voltages and limits) Of course, I don't know about all chips. But basically it would be a good way to destroy the Pi.
A possible solution would be to put a prototyping hat with an extra-long header between the Pi and your screen, and take the power from that. Or, if you're willing to solder, then you can solder to the bottom of the header on the Pi, but you have to know what what you're doing.
A better solution would be to use another power supply. You would need to join the grounds, though.
A "logic level converter" will allow you to convert the 3v3 I/O pins on the Pi to 5v ttl level. These are commonly available from vendors that make hobbyist or "maker" electronic modules, such as SparkFun and Adafruit. These devices typically have to be connected to power on both sides (3v3 on the Pi side, 5v on the device side). You will have to read the specs of the device to decide if the 5v circuit will have enough drive to power whatever you are trying to switch on and off.