How do I make my network secure

In addition to Ikrupp’s reply, you might find this additional info from Apple helpful.

https://support.apple.com/en-us/HT202068

1. Use WPA2 or WPA3 security on your WiFi router. Check your router’s manual for information.
2. Use a password that is not easy to guess. Make it at least 8 characters long. WRITE IT DOWN and save it.

For using public WiFi only connect to hot spots that display the padlock icon and require a password. Do NOT use public WiFi that does not require a password, like most retailers/restaurants, etc. Using those networks leaves you wide open for anybody to snoop on your connection.