<PackageReference Include="Microsoft.Extensions.Configuration.Abstractions" Version="2.0.1" />

IConfiguration

public interface IConfiguration
Represents a set of key/value application configuration properties.
string this[string key] { get; set; }

Gets or sets a configuration value.

IEnumerable<IConfigurationSection> GetChildren()

Gets the immediate descendant configuration sub-sections.

IChangeToken GetReloadToken()

Returns a IChangeToken that can be used to observe when this configuration is reloaded.

IConfigurationSection GetSection(string key)

Gets a configuration sub-section with the specified key.