How to install shader packs:
- Install Optifine (Download Link)
- Download the shader pack you want
- Copy the shader pack's zip file
- Go to %appdata% in the windows search bar
- Open the .minecraft folder
- Open the shaderpacks folder in the .minecraft folder
- Paste the shader pack in the folder
- Launch Minecraft with the Optifine profile
- Go to the video settings, then click Shaders
- Select the shader pack you want to use