Open Krita
Go to the brush preset docker
Click the brush settings icon if needed
Open the Resource Manager
Click Import Resources
Select the brush pack file
Confirm the import
Restart Krita if prompted
Download brush packs from trusted sources
Install brushes by dragging the brush file into Krita
Use the brush preset list to find the new brushes
Refresh resources if the brushes do not appear
Check the brush tag or category for imported brushes