Gray Wobbly World Shaders is a shader pack. It turns the whole game black and white and makes the screen warp and bend while you walk. Like any shader pack, it needs a shader loader such as Iris or OptiFine. It will not do anything if you put it in the resource packs list.
Put the Pack in the Right Folder
1. Launch Minecraft with your shader loader installed.
2. Go to Options > Video Settings > Shader Packs.
3. Click Open Shader Pack Folder. This opens the shaderpacks folder.
4. Drop the Gray Wobbly World Shaders file into that folder. In most cases you can leave the zip as it is. You do not need to unzip it.
5. Go back to the Shader Packs screen. The pack should now appear in the list.
Activate It and Check It Works
1. Click the pack in the list, then click Apply or Done.
2. Load into a world.
3. Check that everything is gray. You should only see black, white and shades of gray.
4. Walk forward a few blocks. The screen should start warping and bending as you move.
If the world still has color, go back to the Shader Packs screen and make sure the pack is the one selected. Selecting a different pack, or choosing the option for no shaders, turns the effect off again.