AN515-54 user pls come, I'm planning to buy an external monitor but I have concerns regarding GPU usage and temps if I use external monitor

I'm thinking to buy Xiaomi G24i, is it compatible for AN515-54? If I plug external monitor does it mean the laptop will use dGPU 24/7 which means the fans will never really be idle and dGPU temps will get hot even when watching a video? Someone with experience please share your usage story..