How do you install shaders in Minecraft?

I want to install a shader for Minecraft but I don't understand. I've already watched videos but don't understand. Lg

You download it and put it in the folder.

Download shader. (It comes as ZIP or 7z).
Unzip the zip file. Windows can do that: Right click on the file and select "Extract".
Then you navigate to the Minecraft installation: To do this, press the Windows key and R, then enter% appdata% \. Minecraft. You should now be in the Minecraft folder.
Now you need Optifine: Download and install it. Then run Minecraft once with Optifine.
In the Minecraft folder there should now be a folder called "shaderpacks". Put in the folder that you just unzipped (NOT the ZIP file!)
Now you have to start MC: Then go to the graphics settings and activate the shader.