The board is powered and switched ON when I try to locate the hardware on Quartus, it is connected to my laptop via an Ethernet cable so I thought the EthernetBlaster would auto detect my board but it does not. Any help would be greatly appreciated.
Is it a dev kit like this one: https://www.intel.com/content/www/us/en/programmable/products/boards_and_kits/dev-kits/altera/kit-sv-gx-host.html
You use USB to program the device through the on-board USB Blaster (USB-to-JTAG bridge), not ethernet. Ethernet Blaster is an Ethernet-to-JTAG-bridge. Are you saying you have an Ethernet Blaster (separate hardware) connected to the 10-pin JTAG interface of the device?
That ethernet is for an ethernet connection to a design already programmed into the device, not for device programming. Like you say, you need a USB cable to program the device.
If it's the board I linked to, it needs USB-A to micro B. See the reference manual: