Like the other commenters said, it’s all about animating overlays. You’ll need to make transparent images on an editing software with the text that you want to show (title, author, warnings, etc.) as well as animating the characters (or using pictures as overlays) and choosing a background. Basically the same as any scene.
Also, there are many editors and artists on the forum and on Instagram that offer pre-made introduction backgrounds and I’m sure some of them would be willing to help you create beautiful text overlays for your introduction, if you’re interested. They might ask for special credits or small payments, though. Always respect the artists!