Throughout my computer consulting career I have set up and improved the security for many Wireless (WiFi) routers. If it’s for a private company or home I use the most security possible to thwart intrusions. A feature that most routers have now is a Guest network. It’s a separate network with a different password and SSID(name) for visitors to use. This way you can keep them off of your main network and your files and folders are safe from them. And you can have different passwords for the main network and the guest one. Or the same if you choose.