We rely heavily on copying and pasting on our smartphones to speed up text editing since there is no mouse and keyboard. As on a computer, copying is usually limited to one item at a time. However, you can copy multiple sets of text using the Samsung keyboard app.
Tap the ellipses (•••) in the top row of On the Samsung keyboard, you will see several icons that you can drag to the top row. Now drag the "Clipboard" label upwards and tap the ellipses again to return to the standard keyboard view.
If you tap this icon, you will see a list of everything you have recently copied. Tap an element to insert it into the active text field. Even better is that screenshots are also shown on the clipboard and can be pasted into supporting apps. However, I've found that this currently only works in the Samsung Notes app.