Another commenter mentioned OpenOffice (http://www.openoffice.org/) but i'd also like to suggest LibreOffice (https://www.libreoffice.org/) as a capable and reasonably compatible alternative to MS Office, which retain the old look of dropdown menus.

If you don't have the need to support very particular features of Office, then it might just be suitable to retain your preferred way of navigating the UI of an office suite app - on my personal computers i have just LibreOffice (with which i finished my bachelor's and master's thesis), whereas on my work computer i have both LibreOffice and Word, for those few exceptions when the latter is necessary.

That said, i can understand why many would also find the ribbon UI to be easy to navigate, should they get used to it. That's why some Office clones, like WPS Office (https://www.wps.com/office/linux/) and FreeOffice (https://www.freeoffice.com/en/) seem to copy it with varying degrees of success. That said, personally i like the open source nature of LibreOffice too and the file format itself not being proprietary.