How to Install and Enable the No Fog Resource Pack
Getting the Pack Into Your Game
Once you have the No Fog Resource Pack file on your computer, open Minecraft and go to Options → Resource Packs → Open Pack Folder. This opens the folder where Minecraft looks for packs. Drop the No Fog pack file (or its extracted folder, depending on how it was distributed) directly into that folder. Return to the game and click Done to refresh the list.
Activating It
In the Resource Packs screen, find No Fog under Available. Click the arrow to move it to Selected. If you use other packs that touch fog or sky rendering, place No Fog above them in the list so it takes priority. Click Done to apply.
Verifying It Works
Load into any world and look toward the horizon. Distant terrain, structures, and biome edges should now be visible without the usual haze. If you still see fog, check that the pack is actually in the Selected column and that no other pack is overriding it. Note that some shaders and mods re-add their own fog independently of resource packs, so disable those temporarily to confirm the pack is working.