How to write shaders?

Hi everyone,
I'm new to coding shaders and need help adding features to a shader I'm working on.
I'm having some problems with removing a checkbox that appeared after adding a drop down list,
and I can't identify which part of the shader language is causing this.

2nd. I want to create a LUT apply shader that populates a list of textures (PNG images) from a specific folder.
Because manually editing a multi-LUT PNG order in Photoshop is frustrating. Since I got a lot of different size Luts.

Is there a way to automatically populate the texture names from a folder with quotation marks and file extensions
into a preprocessor dropdown in my shader? Then can quickly use Luts
without stacking them from a custom folder.
Maybe press a name from that pre-processor window
and it applies it to the top name field ( if I have many fields ) automatically figures the size.
Maybe the new "Add-on" could do this? (I don't know how to make a Add-on).

I might just end back editing multi Luts.

I'm trying to improve this shader but don't know the do's and don'ts of shader writing.
I've looked into HLSL and GLSL but find them confusing.
So far I been mixing matching different shaders to piece together a Frankenstein shader.

Any tips or advice for a beginner is appreciated.
Maybe a user made a indext. Or maybe this is partly a feature request for Reshade.  Thanks.