Answer:
Enter or Return key
Step-by-step explanation:
In many applications such as Microsoft Word, when editing or creating a text layer in a document, pressing the 'Enter' key, or alternatively known as 'Return' key, sends the cursor to the next line or creates an entirely new line which may by consequence create a new paragraph.
PS: For programs such as MS Word, pressing the enter key may move to the next paragraph rather than a new/next line. In such programs, to go to the next line, 'Ctrl' key followed by 'Enter' key should be pressed.
Hope this helps!