By generating them in a file (SRT, VTT) that will be attached to your video when published on social networks. In this case, the social network will manage the display according to an unmodifiable standard (white text on a black background). The main advantage of this solution is that most social networks use the text contained in the file to improve your video's referencing.
The other way of subtitling a video is to embed the text directly into the video. The advantage is that you can apply your own graphic guidelines (font, color, size, background, location).
Customize your first video as you wish, then generate your video. Starting with this new version, you'll be able to create a template that saves all your personalization settings, which will be automatically applied to your videos.
The subtitle format automatically adapts to the format you apply to your video (16:9, 1:1, 9:16, 4:5).
Yuzzit lets you customize the placement and display of your subtitles (font, size, color, background, etc.). Once finished, you can generate a copy of your video with the subtitles embedded in the images.