Intro:-

Calendars are used to display calendar data on the terminal. Spectre.Console is a .NET library which is used to create console applications. Spectre.Console is rendering the calendar on the terminal.

Steps:-

with few commands and also a few lines of code, you can display a high visual calendar on the terminal. The steps are given below.

Create Project

>dotnet new console -o cliapp

Install Nuget Package

>dotnet add package Spectre.Console

Create object

var rule = new Rule("[red]Calendar CLI App [/]");

Add some styling code

calendar.BorderStyle(Style.Parse("Magenta3"));

Calendar Events

You can add an event to the calendar. If a date has an event associated with it, the date gets highlighted in the calendar.
calendar.AddCalendarEvent(2023, 2, 5);

api docs

Calendar AddCalendarEvent(int, int, int)
which is year, month and date respectively.

Render on console

AnsiConsole.Write(calendar);

Conclusion:-

To render a calendar, create a calendar object, and add some styling code according to the app's requirement. Complete the app by passing the calendar to a console's Write method.
The full source code is on GitHub.