Sir if you want the channel to grow fast then you should upload shorts as much as possible. If you upload 10 short videos a day, 3 of them will go viral. This is my personal experience on YouTube.
This is not a difficult task. You can install Kinemaster on your phone and convert any video into YouTube shorts by editing kinemaster. For example, if your video is ten minutes long and is a computer screen video, you can edit the video on kinemaster screen 9: 3 and make that video into shorts.
or you can use any other video editor
You can see in the picture below how I grew my channels

https://www.youtube.com/channel/UCTTQLCT6PJOeVyX8IDFx0tA/videos