How do i create a 2d Surface fake lighting grid shader

I been working on a game for a very long time using game maker studio but I moved into unity
I prefer coding c# to gml script.

but the main issues is I could never figure out how to recreate the surface lighting from gamemaker studio,
I done tried point and spotlights with Cookies but that didn’t work for what I am going for.

here is 2 images of what i have before

if there are any ways of recreating this like, i never learned unity shaders but if i need to I will learn it.

Take a look at this

I’d guess OP is going for a pixelated light look, not for a smooth one that normal mapping would produce.