.net support for xml & xsd is waning. most is around the xsd tool.
https://learn.microsoft.com/en-us/dotnet/standard/serialization/xml-schema-def-tool-gen
and the serialization libraries.
https://learn.microsoft.com/en-us/dotnet/standard/serialization/xml-and-soap-serialization.
you use the xsd tool to create classes the xml can serialize to and from. you add this classes to you project. I often make a separate project for these files. you than can use them as the target type for serialization.