Updated README with Table Of Contents (#18056)

Closes #18055

README.md

@@ -4,6 +4,42 @@
 
 # Welcome to the Windows Terminal, Console and Command-Line repo
 
+<details>
+  <summary><strong>Table of Contents</strong></summary>
+
+- [Installing and running Windows Terminal](#installing-and-running-windows-terminal)
+  - [Microsoft Store \[Recommended\]](#microsoft-store-recommended)
+  - [Other install methods](#other-install-methods)
+    - [Via GitHub](#via-github)
+    - [Via Windows Package Manager CLI (aka winget)](#via-windows-package-manager-cli-aka-winget)
+    - [Via Chocolatey (unofficial)](#via-chocolatey-unofficial)
+    - [Via Scoop (unofficial)](#via-scoop-unofficial)
+- [Installing Windows Terminal Canary](#installing-windows-terminal-canary)
+- [Windows Terminal Roadmap](#windows-terminal-roadmap)
+- [Terminal \& Console Overview](#terminal--console-overview)
+  - [Windows Terminal](#windows-terminal)
+  - [The Windows Console Host](#the-windows-console-host)
+  - [Shared Components](#shared-components)
+  - [Creating the new Windows Terminal](#creating-the-new-windows-terminal)
+- [Resources](#resources)
+- [FAQ](#faq)
+  - [I built and ran the new Terminal, but it looks just like the old console](#i-built-and-ran-the-new-terminal-but-it-looks-just-like-the-old-console)
+- [Documentation](#documentation)
+- [Contributing](#contributing)
+- [Communicating with the Team](#communicating-with-the-team)
+- [Developer Guidance](#developer-guidance)
+- [Prerequisites](#prerequisites)
+- [Building the Code](#building-the-code)
+  - [Building in PowerShell](#building-in-powershell)
+  - [Building in Cmd](#building-in-cmd)
+- [Running \& Debugging](#running--debugging)
+  - [Coding Guidance](#coding-guidance)
+- [Code of Conduct](#code-of-conduct)
+
+</details>
+
+<br />
+
 This repository contains the source code for:
 
 * [Windows Terminal](https://aka.ms/terminal)