Razer Blade Stealth QHD+ & 4K Monitor

I own Razer Blade Stealth (13.3" QHD+, Early 2018) and I have recently bought a 4K Monitor, LG 27UK650. When connected the signal is not clear, having a snowy effect on each movement and often gets disconnected when heavier process takes place.

I understand that they do not have the same resolution and cannot have the same refresh rate of 60 Hz when connected using an HDMI cable.

Is there a solution to this problem? Would a USB-C Hub solve this problem?

Waiting for your suggestions or possible solutions.

Thank You!!!