Now that macOS Ventura has been released, it’s become more difficult to access the macOS Monterey installer for those who still need it. Fortunately, macOS Monterey has not been removed from the App Store and it is still available for download. Apple has a KBase article that shows how to access the macOS Monterey page in the App Store, available via the link below:
https://support.apple.com/HT211683
To access the macOS Monterey page directly, please click on the link below:
https://apps.apple.com/us/app/macos-monterey/id1576738294?mt=12
That link should open the App Store and take you to the macOS Monterey download page.
In the event that you’re blocked from downloading macOS Monterey, you should be able to download it in a virtual machine. I have a post on how to do this, available via the link below: