Problem with Mission Control when using an external monitor on MacBook Air

Hello everyone. I have a question that I couldn't find the answer to anywhere. I have a MacBook Air 13 M4. I connect an external monitor via HDMI, gaining additional workspace, and it works wonderfully. However, my question is this: I want to watch a video on one monitor while working with other applications on my laptop. But there's something that really annoys me: when I swipe up with four fingers to switch between desktops on my laptop using Mission Control, the same action happens on the monitor where the video is playing. How can I change this?