The minimum bet or raise for that round is 2K (the amount of the big blind).
To "raise", you are essentially 'calling' + 'betting at least the minimum'.
Thus, you may call 600. Or you may raise 600+2K=2600.
"Complete" is not an option in a no limit game.
Reference - e.g. Robert's Rules definition of "Complete the Bet":
COMPLETE THE BET: To increase an all-in bet or forced bet to a full bet in limit poker.