Just because you found an image on the internet, doesn't mean it is there legally or is free to use. Check the website about their policy on reusing their images. For example, here is a statement from NASA, about using their images and logo: https://www.nasa.gov/nasa-brand-center/images-and-media/ You can also reach out to the artist to get permission, if you want to use something from their website.
Try to find images with a Creative Commons License (CC). These images are free to use, usually with credit given to the creator (CC-BY).
Copyright and use of protected images in AI is a rapidly evolving issue. The US Copyright Office has issued a report about the use of copyrighted images in AI, and more will be determined in the future as new legal actions emerge. https://www.copyright.gov/ai/
In summary: don't assume you can use any image, get permission and give credit, and don't feed copyrighted images into AI.
MLA (Modern Language Association) is the citation style most used in the humanities, and in many undergraduate writing courses at Rutgers. Another style frequently used in writing courses is APA (American Psychological Association). Below are resources to help you cite using these styles and others.
APA Formatting and Style Guide From the OWL at Purdue
APA Documentation Guide From the Writing Center of University of Wisconsin-Madison
APA Publication Manual Tutorials and More https://libguides.rutgers.edu/learningapa
Zotero - a free online citation manager https://libguides.rutgers.edu/zotero