im trying to authorize my MacBook Air to download purchased contente but I don't see the authorization option anywhere. what can I do?

See the following from Authorize or deauthorize your computer for iTunes Store purchases - Apple Support

How to authorize a Mac or PC

Before you authorize a Mac, update it to the latest version of macOS. On a PC, update to the latest version of iTunes for Windows.

1. On a Mac, open the Music app, Apple TV app, or Apple Books app. On a PC, open iTunes for Windows.
2. Sign in with your Apple ID.
3. In the menu bar on your Mac or PC, choose Account > Authorizations > Authorize This Computer.
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