Not sure if with "should" you are talking about some kind of ideal world. But in 2022 in the real world, this cannot be done. Online Word is a joke. I would like to use it (because I hate MS Office, so if I could go without having it installed and taking room in my HD and start menu, it would be great) but it's unusable even for my quite basic needs. A sister comment talks about advanced stuff like Excel macros, etc.; but even very basic functionality is not available.
For example: right now, it's impossible to edit a document online with Track Changes without showing all the changes (which makes documents practically unreadable). And you don't even have pages online, documents are shown with a continuous layout where it's difficult to know where pages start and end.
For example: right now, it's impossible to edit a document online with Track Changes without showing all the changes (which makes documents practically unreadable). And you don't even have pages online, documents are shown with a continuous layout where it's difficult to know where pages start and end.