Shader not rendering a specific color

Hello everyone, I’m totally new to shaders, I never made one

I was wondering if it’s possibile to have a shader that renders an unlit texture normally except a specific color, which should be rendered as transparent

kinda like a greenscreen thing and i want to make the shader to render rgba(0,0,0,0) instead of rgba(0,1,0,1)

I know i could just use a texture with alpha, but i need this for a videotexture on mobile, so i thought this was the only option

Thank you in advance for any hint or answer provided

Chroma Key is what you want to search for. There are a number of assets on the store and a couple of free options on the forum and elsewhere.