how to take screen shot of a textarea tag and save it as an image in a folder?

i have a <textarea> HTML tag and i need ; when a user write something in the <textarea> , and click on a button , javascript codes take the paragraph and change it to an image and save it in user desktop or a folder with a path .

this is the adress of a simple webpage , it’s just HTML and i need Js code for this function : https://www.20ide.com/