Hi,
I’m relatively new to Unity. A few months into it.
I’m looking at the Viking Village Tutorial project, and the lighting, colors, fire, smoke effects, vegetation all look great. But nothing is really explained in how everything is set up or working in the project. Feels like there is a big explanation in the tutorial missing. The end result is shown, but no “tutoring” is going on.
A little more specifically, I would like to for instance convert Viking Village to the Built-In pipeline and set it up in the same way so it looks as good as it does in the current URP. From what I can tell, even though URP is said to be “better” and the future, the built-in is the past, there are no actual rendering features (that Viking Village) uses that shouldn’t in theory be able to be duplicated in built-in.
So, I naively changed the pipeline from URP to built-in. Everything went pink. Then I changed almost all the shaders to “Standard (with Specular Setup”, and the end result was I could see the scene, but it did not look nearly as good as before. But I don’t know what is missing.
Viking Village is not explained, so it is impossible to know how to set up a new scene to look as good as Viking Village.
Any help appreciated. 
most of examples require you to look at how they are prepared. So they will provide an object that have the setup as it needs to be and you need to look at how it is.
that asset is used by various youtubers to create tutorials so you can check on youtube. Some of them may explain part of the asset.
the issue with the pink materials is that each unity render mode URP, HDRP, built in, require different materials, textures shaders.
You are the first one that want to convert from URP to built in. Everyone want to convert from built in to URP and HDRP
There is a convert tool but it is only for the second option
https://docs.unity3d.com/Packages/com.unity.render-pipelines.universal@13.1/manual/features/rp-converter.html

first can you say what “Viking Village” asset you’re talking about as the asset store has many of them with this same name
for the pink, your correct just switch the shaders and in some case URP shaders settings may not be = such as alpha clipping … also in unity shaders some changes in color tint may change as they use different properties such as _Color vs _BaseColor… you could adjust as needed
i would also suspect post processing is different and you would need to remake a new post process profile for Built-In changing color curves in Unity Built-In will also help see Unity - Scripting API: Rendering.GraphicsSettings.lightsUseLinearIntensity (unity3d.com) and set it as = True
Create a new Unity project using the 3D(URP) template in the Unity Hub. Then get the Viking Village from the Assets Store and import it in that project. Let it override and install what it needs. That way it worked for me.