Suppose I transfer all my pictures from my mobile phone to my laptop and first delete some of them on the laptop (also from the trash). Can you then somehow restore these images?
Yes, there are programs like Recuva that can be used to back up images from the hard drive, USB sticks or memory cards, for example, but these only work to a limited extent, so if the images were deleted a long time ago, it may no longer be can be restored.
Often when data is deleted, only the information on the data carrier is deleted, where it is located, so that the data can then be partially or completely restored, provided that it has not already been overwritten (but depends on the data carrier).
Files are only "deleted" from the index of the hard drive, so your box knows that the place where they were can be rewritten.
If that location has not yet been overwritten, the files are usually recoverable.
Depending on the hard drive, this location has to be overwritten several times. Allegedly 1x is enough, but with my external hdd's were nögit several times.
If your drive to which you dragged your images is an ssd, I would overwrite it with a tool, e.g. Let the ccleaner stay. The write cycles on an SSD are limited.
Next time delete it directly with e.g. The Ccleaner IN THE PAPER BASKET. If you want to have your pictures safely deleted now, you would have to overwrite THE WHOLE hard drive, or you can restore them with recuva and then delete them from the trash with a tool.