It is a big celebration for AC Milan, as at last season they got kicked out in the group stage after finishing fourth in group C with only one game won. This season they got so much improvement having played against RB Salzburg , Chelsea and Domino Zagreb and their worst performances was against Chelsea both home and away. Giroud made soo much contribution in seeing the proceed to the next stage. He made the biggest contributions equating his goals to his assists.
But unfortunately Milan is a non-seeded team that will most likely face other top teams in the last 16. Milan's journey in the last 16 may be very difficult considering the current seeded team looks very strong like Manchester City, Bayern Munich or Real Madrid.
I wouldn't be surprised if Milan's journey had to stop in the last 16 this season if Real Madrid, Bayern Munich or Manchester City were the opponents. But if it's Porto, Tottenham or Benfica then I think Milan have a chance to qualify for the next round.
I must say that in the 1/16 finals there are actually no "weak" teams.
Yes, there are Rangers teams with a score of minus 20 in goals scored, but all the teams that made it to the 1/16 are either champions of their leagues or silver medalists.
Benfica generally bypassed PSG in the group, although the possibilities of the latter are much higher.
Tottenham also went through a strong group and only in the last match left the group.
So whoever is Milan's opponent, it will be an extremely strong team, but there are no invincible teams, so let's wish Milan good luck.