Videos in portrait and landscape format?

I recorded a video with my cell phone. In landscape format. However, the video is displayed in portrait format on my mobile phone and laptop. What can I do? So I always have to turn my head by 90 * so that I can watch the video properly.

So I quickly tested it with my smartphone. The smartphone initially determines whether the video is portrait or landscape, depending on whether the phone registered when the video started that it was held in portrait or landscape. The first way I found is to shoot the video using the VLC player that can be downloaded for Windows.

Tools → Effects and Filters → Video Effects → Geometry

Thanks, but I solved the problem myself. But thanks anyway