You can activate Wicked Wolf's last ability even if it's already tapped.

You can activate Wicked Wolf's last ability any number of times while its first ability is on the stack.

If the target creature is an illegal target when Wicked Wolf's first ability tries to resolve, the ability doesn't resolve. If Wicked Wolf is no longer on the battlefield, the target creature won't deal or be dealt damage.

If an effect refers to a Food, it means any Food artifact, not just a Food artifact token. For example, you can sacrifice Tough Cookie (an Artifact Creature — Food Golem) to activate Maraleaf Rider's ability (an ability with "Sacrifice a Food" in its cost).