There are many ways to delete objects from your drawing and clean up the display.
Remove Unused Definitions, Styles, and Objects
PURGE. Some of the unnamed objects you can purge include block definitions, dimension styles, layers, linetypes, and text styles. With PURGE you can also remove zero-length geometry and empty text objects.
You can remove unused named and unnamed objects withYou can remove the plus-shaped markers called blips and stray pixels that may be left over from some editing operations from the display area.