What spikey_richie suggests will reset the whole context menu back to the look from Windows 10 which might be what someone wants but does not answer the OP's specific question.
I was looking for a way to only get the "Create New Text Document"-option back. Found this great page: https://www.tenforums.com/tutorials/24412-add-remove-default-new-context-menu-items-windows-10-a.html
And used the "Restore_New_Text_Document_context_menu_item.reg"-file which worked great.
To only restore what the OP asked, the following .reg file is the only thing needed. A sign out/sign in OR reboot is needed for explorer.exe to pick up the change.
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\.txt\ShellNew]
"ItemName"=hex(2):40,00,25,00,53,00,79,00,73,00,74,00,65,00,6d,00,52,00,6f,00,6f,00,74,00,25,00,5c,00,73,00,79,00,73,00,74,00,65,00,6d,00,33,00,32,00,5c,00,6e,00,6f,00,74,00,65,00,70,00,61,00,64,00,2e,00,65,00,78,00,65,00,2c,00,2d,00,34,00,37,00,30,00,00,00
"NullFile"=""
[HKEY_CLASSES_ROOT\txtfilelegacy]
@="Text Document"