spectre.console/docs/input/quick-start.md

Title: Quick Start Order: 1

The fastest way of getting started using Spectre.Console is to install the NuGet package.

> dotnet add package Spectre.Console

After that you will need to reference the Spectre.Console namespace. Once that is done, you can start using all the available features.

using Spectre.Console

public static class Program
{
    public static void Main(string[] args)
    {
        AnsiConsole.Markup("[underline red]Hello[/] World!");
    }
}