Welcome to Android Central! I'm not too familiar with the preinstalled software on Samsung devices, but are you referring to the Clipboard function that allows you to temporarily store text and then paste it elsewhere? Or is there some "My Clipboard" app that you're looking for?
If there is text that you copied to the Clipboard, then open any document with Google Drive, or open a note with Google Keep, then long press any blank part of the document until the option for "Paste" appears. This will only happen if there is any text stored in the Clipboard. If "Paste" doesn't appear, then the text in the Clipboard has been purged.