Google Lens can be treated as an image-based search engine. You take a photo and open it. It will scan the photo and show all the text and numbers in that image. You can simply copy them to some other documents. Secondly, Google Lens will scan the photo that you clicked or supplied from your gallery and gives details about that pic, or at least it will display some related images. You can also use this app as a QR code scanner as well.
If you are in a new city, you can click the photo of a restaurant and get its details like its cuisine, working hours and customer reviews, and more.
In my personal experience, I use it to copy the text from an image, or else, I will be using Google Lens to know more about an unknown bird, tree, or any strange insect to learn about it like its scientific classification, binominal name, place of its origin, etc.