"There are no restrictions on any use as long as a user adds a watermark to avoid any copyright infringement or plagiarism."
This is very confusing.
Traditionally, adding your watermark to images you create manually, is normally something an artist does to prevent others from using your images.
Adding your watermark to an image you create with an AI generator, may prevent others from using your AI images, but adding your watermark to these images does not protect you from being accused of copyright infringement or plagiarism, as the images are created by AI and who knows where AI got parts of those image from. A watermark in the case of AI art seems irrelevant to the question of whether we can use images generator by Bing Image Creator (now Bing Copilot) .