1. The qualification of the World Cup champion is not only related to the competition results, but also related to the strength and level of the participating teams. Although France is the champion of the 20 18 World Cup, if their performance in this World Cup is not good enough to get the top two in the group, then they can't qualify directly.
There are many teams participating in the World Cup, and the competition is fierce. The champion may not guarantee promotion. Even the champion team may meet strong opponents in the same group. If they can't qualify for the group stage, they need to take part in the play-offs to win the last chance.
Therefore, the World Cup champions also need to compete fiercely in group matches and play-offs to qualify.