There is option to add text into lightbox when the image is chosen and in preview position?
Yeap, there is
When you choose which media goes in to the lightbox element, there’s an input field called “Caption”:
I saw that there is a place only one line.
There is any way to add more text or edit it?
Not when using the lightbox widget.
You can do this manually by creating the image elements and placing text elements below them.