Learner bikes are designed to help your child learn to balance and be ready to progress to riding a two wheel bicycle without the need for stabilizers in due course.
Your child will scoot along whilst learning to balance. When they gain enough speed and confidence they will put their feet up onto the platform.
As the learner bike slows down or the child feels less stable they will automatically put their feet back onto the ground. If the child does drop the learner bike there are no pedals to bash their ankles.