The 19-year-old became the youngest France player to score in a major tournament when he fired home from close range in the first half in Yekaterinburg.
Pedro Aquino hit the post for a lively Peru, who are still waiting for their first World Cup win since 1978, and the South American side can no longer qualify from Group C.
The 1998 tournament winners are top of the group after the second round of matches, two points ahead of Denmark and five in front of third-placed Australia, meaning they will now progress.
They face Denmark in their final game to determine who will top the group, while the Danes need just a point to progress.
Odds correct as of 2050 BST 20/06/18