Masto.NET is a .net standard library for Mastodon written in C#.
If you prefer to browse code, you can go the the sample project : https://github.com/glacasa/Mastonet.SampleApp
The package is available on Nuget : https://www.nuget.org/packages/Mastonet
Run the following command in the Package Manager Console :
Install-Package Mastonet
Read the docs :