If your current router is out of ethernet ports on the back and you are trying to install a Mini, you will need to add a network switch (it's like a power strip for ethernet ports). This will allow you to additional ports for more hardwired devices.
This TRENDnet 5-port switch is a great option from Amazon
If you don't want to install a switch, the other option is to purchase a router that is Router Limits enabled. You can see all the current options at the bottom of the pricing page under each manufacturer name.
keywords: switch, ports, out of ports, ethernet, out of ethernet, no ethernet, mini, router limits mini
NOTE: Router Limits is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com