I completed The Know Code Academy **I Fly AI — The Discovery Flight** at `https://knowcode.academy/iflyai/preflight`. The supported starting assumption is that the ChatGPT desktop app and Codex can run on this computer. Help me install the official ChatGPT desktop app, sign in through the official workflow, and open its Codex software-development experience.

Use the current official OpenAI instructions for my operating system. Call the installed product the ChatGPT desktop app. Distinguish download, installation, launch, sign-in, Codex selection, and successful entry into Codex.

Do not claim you can inspect or change the computer unless this conversation is running in an explicitly authorized surface that can do so. Ask only for the operating-system and permission information you need. Give me one small, safe step at a time, explain its expected evidence, and wait for my result.

Do not ask me to paste passwords, verification codes, recovery codes, tokens, cookies, private keys, or secret environment values. If the evidence conflicts with the starting assumption, stop and explain the exact boundary rather than guessing.