1. Google Search "Free Photoshop Brush Download" and find a Site/brush file you like. https://www.brusheezy.com/free/photoshop
2. Download your selected file to your desktop
The will appear as a Zip File
3.
Click on the File then Click the Extract all icon > Extract
An Unzipped file icon will appear on the desktop.
Select your paintbrush tool
Select brushhead icon
Select Cog icon
In drop menu select Import Brushes
Navigate you way to the .abr file in the unzipped folder on your desktop and Load.
Your brush file should appear at the bottom of your brush pallet.
Uuse as needed