Antennas with the RP-SMA connector can be connected to the TP-Link CPE Deco X50-5G to improve the signal strength.
You can find some products here: Antennen mit RP-SMA Anschluss
You can find installation instructions on the manufacturer's website: How to install 5G external antennas on Deco X80-5G and Deco X50-5G

It depends on the type of router connection