OKIOCAM is a plug-and-play USB camera that doesn't require installing any software to record video. You can use the Windows 10 Camera app to record .mp4 files. Here's how to do it:
Step 1. Plugin OKIOCAM and launch Camera App. You can type 'camera' in the search bar to quickly access to this App.
Step 2. Click the top-right icon to change the camera.
Step 3. Click the recorder icon to switch to the recording mode.
Step 4. Click the recorder icon again to start recording.
Step 5. When you finished recording, click the stop button. The .mp4 files will be saved in the camera roll.
Step 6. In the camera roll, click the top-right icon > Open Folder. You should be able to see the recorded .mp4 files.