Yes the winning team advances to the quarter finals . And the loosing team get eliminated . but if they time they go to extra time and if there still tied they go to penalties.!

Yup! That's about it. The only time a losing team will play again is for the 3rd place match.

P.S. The knockout stage begins tomorrow :)

They play for 45 minutes, have a break for 15, and play again for another 45.
The team with the most goals qualify to the Quarter final, and the losing team have to go home, they're eliminated.
But if after the 90 minutes of play if the game is a draw, they'll have to play for another 15 minutes, have a 5 minutes break, and play for another 15 minutes, and the winner goes through, and the losing team at that time is out of the world cup.
But if it's still a draw they'll have to take 5 penalty kicks, the best out of 5 each, will qualify, and the losing team goes out.
And if it's still even like both scored 4 penalties out of 5, then it goes to sudden death.
A penalty missed, and the other team scores then it's over and we have a winner, and if they both miss or score, then they'll cary on until there is a winner.

It's not round 16. It's the 2nd round.

You might have heard it referred to as "the last 16" (ie the last 16 teams remaining in the tournament compete in the 2nd round).

In the second round, and then the quarter final - the team that wins goes through to the next round, the team that loses is eliminated.

Once we're into the semi final - The teams that win go on to the final, the teams that lose face each other for 3rd place.

Round 16 is deep, you already missed 1,2,3,4,5,6,7,8,9,10,11,12,13,14 and 15!