What computer software and hardware knowledge do you need to do computer work in a 4-star hotel?

It depends on what you are mainly responsible for when you go. If you are a database worker, you should know more about it. But generally speaking, getting a database is very simple. It's just a software, you can use it. If it is network maintenance, it is certainly useful to learn ccna. There is too much knowledge about computers to learn. As long as you study while working, you can find the right direction.