Although LibreOffice 24.8.2 is free, and it is developed as a Microsoft Office clone with mostly document compatibility, there will be a learning curve owing to a different menu structure and user interface. This version of LibreOffice requires macOS Catalina or later, so you are covered with Monterey.
LibreOffice has created extensive documentation, written with LibreOffice Writer, that attempts to flatten the learning curve somewhat.
An alternative to LibreOffice, and also a Microsoft Office clone, is the free trial but paid SoftMaker Office 2024 for Mac. It is supported on macOS Mojave onwards. Unlike LibreOffice, the SoftMaker product has a product support team behind it.