La forma mas sencilla es usando el atributo de clase [Serializable]
https://docs.microsoft.com/en-us/dotnet/api/system.serializableattribute?view=netframework-4.8
https://www.c-sharpcorner.com/article/serialization-and-deserialization-in-c-sharp/
https://docs.microsoft.com/en-us/dotnet/api/system.serializableattribute?view=netframework-4.8
https://www.c-sharpcorner.com/article/serialization-and-deserialization-in-c-sharp/