Three Zyxel NR5103E poor internal WiFi

[slinkydonkey]

So I live in a little coach house 2 bedroom style falt and I have noticed unless I am sat in the same room as the "Three Zyxel NR5103E" I will get packet loss. This is 2024 why is this router so bad! can I fit external antennas on it ?

To clarify this is to improve the internal 2.4 Ghz signal (the 5G signal isn't great but im not spending £150 on an external 5G antenna). 

[slinkydonkey]

Correcting it's not the router is my crappy "Aqara Video Doorbell G4"

[Simon1402]

I would recommend splitting the 2.4GHz and 5GHz WiFi bands. Only use the 5GHz for anything that is both high volume and shirt distance.