Why there is a list of errors/warnings when i Import Gaia?

[goodGraphicGuy]

Gaia will still work but it looks messy that my console always gets these kinds of warnings/errors. They are clearable and i can push play but they are messy. Why does it happen? It happens with almost all assetstore products i bought. But Gaia Pro 2021 also.

[goodGraphicGuy]

Here is another picture. This time the warnings are red. They are clearable but i dont understand why they happen. These ones dont say Gaia, or Procedural worlds but they happened instant after i imported Gaia, and it's a new HDRP project and the only thing i imported was gaia pro 2021.   I'm also worried because the last time i tried to build a game( i haven't made many), it wouldn't build if there were errors. So i wonder if it will be able to build if i get these kind of errors.

[goodGraphicGuy]

PS. I Use Unity 2021.1.28......And i've tried 2021.1.16, then i heard in discord Official Unity Channel that errors like this may mean the asset was not made for my version of Unity or HDRP......well,  but then i tried an LTS version too 2020.3.32 LST and i get the same errors when i import. So then what are we supposed to do?

[Peter]

Hi, these kinds of errors happen because the shader compilation / import process of unity is a bit overzealous with warnings and errors. When looking into those it often turns out that the kind of warning that is being produced "does not make sense" at the portion of code it is pointing to, and it can then take hours to analyze and try to find a workaround so that this warning is not created on import anymore. These warnings and errors can then also be different depending on unity version and render pipeline used. 
Sometimes it is possible to fix those by making simple adjustments to the shaders, sometimes it is not and it would either mean a large investment of programming resources into researching why those errors happen to potentially fix them eventually. We usually look at those and try to fix them within reasonable effort, but if it goes off the rails we would rather invest the resources towards developing new features and improving existing ones.
These errors should not affect you beyond appearing once during import. A build error would have a different cause that would need separate analysis.