How do I use and create shaders?

I’m a beginner in deep ar.
The thing is, I need ‘LUT with alpha mask’ to create a material. But I can’t find it no matter how much I look for it. How can I get this shader? Does it require scripting? I’ve been stuck for hours.
Also, how do I apply the shader? When I put it in, it says Miscellaneous in the Assets window. How do I load it as a shader? Is there something wrong?