Hello experts !

I would like to protect with a password my complete File where I have all my MSW documents. Not just one or two documents, not just a few documents but the whole file containing all of them, there are hundreds of MSW documents inside that file.

Is there any way to protect it with a password ?
I have been exploring the option "General Tab", "Attributes" and then I see two options: "Read only" and "Hidden", I suspect the "Hidden" option is for protecting the whole file but since I am not sure I don't want to click on it. Can you tell me please what is that option for ? and then also if I click on it how can I have access to it afterwards ?