Here`s what you can use to power your Raspberry Pi 4
(Android Central)

You might be tempted to use an old phone charger (or even a new one!) to power your Raspberry Pi 4 but you really shouldn`t. These little computers need a steady and clean source of power at 5 volts and 3 amps, which means any old wall plug that has support for fast charging can`t provide. The good news is that a dedicated power supply for your Raspberry Pi is nice and easy on the wallet. Basic and perfect CanaKit Raspberry Pi 4 Power Supply Staff pick CanaKit makes some of the most popular parts for the Raspberry Pi and this power supply is designed specifically for version 4. It`s a perfect choice if you just need a way to keep things powered up. $10 at Amazon Mighty Mini IBERLS 5V 3A USB-C Power Supply This power supply from IBERLS provides the regulated power your Raspberry Pi 4 needs and the adapter is up to 20% smaller than the competition. If you need to plug things in where space is at a premium, this is the one to buy. $10 at Amazon Kit and Kaboodle ...