@RequestScoped
public class RequestBean {
}

@ApplicationScoped
public class ApplicationBean {
}

services.AddScoped<ICharacterRepository, CharacterRepository>();
services.AddTransient<IOperationTransient, Operation>();
services.AddScoped<IOperationScoped, Operation>();
services.AddSingleton<IOperationSingleton, Operation>();
services.AddSingleton<IOperationSingletonInstance>(new Operation(Guid.Empty));
services.AddTransient<OperationService, OperationService>();

[RequestScoped]
public class RequestBean {
}

[ApplicationScoped]
public class ApplicationBean {
}

To use:

[Inject]   // Similar to CDI @Inject
private RequestBean requestBean;

And more ....