You can use the antenna as it will work on the RF frequency.
The MOBO may only have 1 port coming out the back but you can get a dummy slot for one of the PCI slot covers that has holes for the SMA connectors to mount to and splitting to separate antennas rather than Y cabling them will result in better signal strength. I figured this out by using a puck w/ 2 leads feeding into it with my gateway device. The speeds went down vs independent antennas.
https://www.amazon.com/dp/B08XNBN7TT/?tag=snbforums-20 - $15 10" pigtails / 2 antennas / slot blank
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There's probably an M2 hidden under the plastic shielding covering the back IO ports. For mine I ordered a board w/o WIFI installed since I had parts lying around to just add it myself to the MOBO and saved $20-$30 by doing so. Sure, it took taking out about a million screws to remove the brackets and shields to get to the ports on the back to insert the pigtails and run the wiring to the card but, it's sleek and is a backup option if needed. Likely not needed though as I have 5 Ethernet ports because I'm using it as a router and some other things at much higher network speeds. The NIC is a 4-port 5GE because the NAS portion of the box runs at ~420MB/s across Ethernet. So, it's a bit custom designed for the speeds at which it can operate with some overhead available for other things to work while copying files back and forth at maximum speed.