I am wondering, can I insert some text in my images? I can’t find a way to insert some text. Please help!
You can insert text by creating a vector layer and use inkscape to add text.
You can also create text in an image editor—Gimp, for example—and copy & paste it into a MyPaint layer. It takes some guesswork to get the proper scale, but you can always undo, change the font size, and then copy-paste again.