If your child is younger than three and a half, we recommend a balance bike or balanscykel. They don’t have any pedals, so your child can simply push along with their feet then glide on two wheels to practice balancing.
Their first “proper” bike should then be gearless and have coaster brakes. Once your child has learned to balance and cycle more independently, their next bike can have a handbrake. Only then do gears become a welcome addition rather than a distraction for the child.