Bandicam is a screen recording program that allows you to record everything on your computer screen. When you finish recording, you can upload the video (including 1080p HD and 4K UHD) to YouTube without any conversion.
If you want to upload the recorded video to YouTube, download the free version of Bandicam from https://www.bandicam.com/downloads/, record the target, and click the Upload button on Bandicam.
Please see the tutorial below to upload videos to YouTube from Bandicam.
YouTube Shorts require videos that are up to 60 seconds long and have a square or vertical aspect ratio.
1. After selecting the Rectangle on a screen mode, lengthen the rectangle recording window vertically. Then, record a video that is up to 1 minute long.
2. Click the [Upload] button under the [Home - Videos] tab and enter #Shorts in the title or description.
If you upload the short vertical video with the #Shorts tag, your video will be uploaded as a YouTube Shorts video.