I have a laptop with an i5-1135G7, can it run 120hz+ external monitor? I saw that it supports 4K @60Hz only.
Hey, Provash.
It should be able to handle a 1080p 120Hz monitor without a problem. I think it should work both with HDMI and DP, but if you want more certainty, use DP.
Welcome, but you would have saved another topic if you had searched for 120Hz 
See the second post here, which indicates that you can but you won’t get the 120Hz