If you don't know someone's name but have pictures of them, there are several ways you can try to identify them. One method is to use a reverse image search engine like TinEye or Google's reverse image search. You can upload the image or enter the URL of the image, and the search engine will show you all the results where the photo is posted. This can help you find other instances where the person has appeared online, and may lead you to information about their name or other identifying details.
Another approach is to use social media or online communities to try to find the person. You could search for local groups on Facebook and post details about the person and where you met them to see if anyone recognizes them. Alternatively, you could try using websites that are designed to help people find each other, like personal ads on Craigslist. You can also search these websites to see if the person you're looking for is actively searching for someone as well.