If you are seeing greyish textures, or ground textures with static, noise, or pixelation, it typically indicates an issue with video card drivers. Updating the drivers often fixes this.
Update Video Card Drivers
Ensure that your computer has current video card drivers.
Drivers are the software that tell the hardware how to run. Out-of-date drivers may fail when telling a piece of hardware (like a video card) how to run a specific type of software (like Fortnite). making sure your video card drivers are up to date can solve many video problems.
The following links contain the most up-to-date drivers for each manufacturer:
Update Windows
Updating Windows can solve many issues that you may have with our games and other apps including connection, installation, and launch issues. This can also help your computer run faster.
Check out this Microsoft article for instructions to update depending on your Windows version: Update Windows
Minimum System Requirements
Older computers may also not meet the minimum system requirements. For more info, check out: What are the system requirements for Fortnite on PC and Mac?