I am building a website that would compile test questions. However, test questions and answers should be entered in LaTeX format with image/gif/audio/video/hybrid files upload features from the device. I found some recommended text editors from stackoverflow, but I couldn't find a free text editor with video upload from the device. Most of them support URL pasting or embedded code. I try to use froala but it requires buying a premium.
You can try Syncfusion Angular RichTextEditor control https://www.syncfusion.com/angular-ui-components/angular-wysiwyg-rich-text-editor
The whole suite of controls is available for free (commercial applications also) through the community license program if you qualify. The community license is the full product with no limitations or watermarks.
Note: I work for Syncfusion.