Nethereum 472 AOT runtime dlls, please check Nethereum releases for more information, extra components, or other versions (net461, net35, netstandard) https://github.com/Nethereum/Nethereum/releases, example of usage can be found at https://github.com/Nethereum/Unity3dSampleTemplate.
To add this package as a dependency just use the github url, more info can be found here: https://docs.unity3d.com/Manual/upm-git.html