LR does NOT contain images, it only contains pointers to the locations where the images were when they were imported, and any adjustments that were made.
The catalog or database DOES NOT contain any images. It is a database, and contains pointers to where the files are located on your computer system. If you delete the files from their folders then they are gone. You don't want to do that. This is a fundamental concept with Lightroom that you need to completely understand in order to move forward effectively.