The Windows 10 is designed to allow users to project visuals to a second monitor is diverse ways. If this doesn't fix the issue, proceed to the next troubleshooting method.
Now check if your PC detects the connected HDMI monitor.
Step 3: Scroll to the Multiple displays section and tap the Detect button. Step 2: On the left-hand pane, select Display. Step 1: Launch the Windows Settings Menu and select System. Luckily, the Windows 10 OS has a 'Detect switch' that lets you instruct your PC to check for secondary/multiple displays manually. If you are trying to connect an old monitor or TV to your PC, Windows might have a problem detecting it automatically.