I’m working with a guy on securing his home network. He has a Moto router that we set the password for so he can get to the settings. What we need to do is set it up so you need a password to access the network. I did this once years ago and can’t remember how now.
I would recommend doing WPA with a PSK as well…something with both alpha and numeric. If you want to really lock it down also put in a MAC filter and disable the SSID broadcast. All of this stuff is fairly easy…let us know if you need any help doing any of that. I think there are a bunch of 'dopers able to do this kind of thingy.