Hi @Reezigt,

Will you be running Ethernet to it from your Router?  You can create whatever SSID's you would like (and multiple ones at that).

If you create an SSID on the EAP245 with the same network name(s) (aka SSID) as your Archer, with the same encryption (e.g. WPA2-PSK) and the same wireless password, your wireless clients will happily roam from one AP to the other.

Manually set the 2.4G and 5.8G radios on each to different channels.  Use 20MHz for the 2.4GHz radios (e.g. 1,6, or 11), and 80 MHz for the 5.8GHz radios (e.g. 36 and 149).

Depending on the location, orientation, and distance between your Router/AP you will likely need to turn down the transmit power of each.  Start with a medium setting on each, and adjust from there.

-Jonathan