>>106325116
https://antongerdelan.net/teaching/3dprog1/maths_cheat_sheet.pdf
note that the shader is actually the easy part, because it's a solved problem (aka you copy and paste the example for rendering a 3D model rig and that includes instancing and bones and normal maps, and maybe PBR).
This is pretty much all the math you need to know:
https://antongerdelan.net/teaching/3dprog1/maths_cheat_sheet.pdf
You will get way more fucked by the graphics API itself, because there is no universal truth, the shader is actually shared between all the graphics api (hlsl/glsl gets compiled to the same spirv, technically interchangeable by API if spirv is supported).
But 3D graphics is a fruitless task. You can do a lot with shaders in unreal engine, since it has a clean node graph system, but making your own engine is tricky because simple tasks like using multiple shaders can be annoying, but if you already spent a couple years learning C or C++, it's natural to pick making your own engine, but it doesn't end well for most who try to make something 3D (also doesn't end well for most people using engines, but at least with engines you have a billion more tutorials).