Startup.cs

public class Startup
{
    // Other Startup code omitted 
    
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddAuthorization(options =>
        {
            options.FallbackPolicy = new AuthorizationPolicyBuilder()
                .RequireAuthenticatedUser()
                .Build();

            // Register other policies here
        });
        
        // Other service registrations omitted
    }
}