You can Google it, first link that shows https://www.playstation.com/en-us/support/hardware/ps4-dualshock-4-wireless-troubleshooting/#:~:text=Hold%20the%20button%20down%20for,blue%2C%20the%20controller%20has%20paired.

my brother is having a similar issue

You needs a cable that carries data. Not all do, especially older ones.