You can download the macOS Monterey 12.7.6 installer package directly from Apple's Software Content Delivery Network (swcdn.apple.com). Once downloaded, running this .pkg file will place the "Install macOS Monterey" app into your Applications folder.
: You need a standalone installer to create a bootable USB without a stable internet connection. Official vs. Third-Party Downloads Macos Monterey Dmg Download Google Drive Free
Then install the desired version: