It sounds unfair of any parent to fail to set for their child the bike seat and the handlebars after buying the bike for that given child. Your child cannot know how to do something unless you first train him or her. This means that to start, you will have to do it for him or her. Here is the guide for you on how to set the seat and the handlebars kids in wheels.
First, you will have to ask the child to sit on the bike with his or her feet on the pedal while at the same time holding the handlebar. Allow him to press the pedal until the lower peddle is at its lowest position. At this point, check to confirm that the child is comfortable without training to hold the handlebar or to keep his feet on the pedal. If not, adjust to create some comfort for the child.
When you have confirmed that he or she is comfortable at that angle, tell the kid to step down with one foot as the other one is kept on the saddle and still he is seated. He or she should do so with ease. If not, lower the seat and push the pedal towards the child until he or she can comfortably hold the handlebar. This helps you to be sure that the child’s safety is guaranteed. In case he loses control, he can step on the ground easily to gain stability.
As you do this, remember there is no harm making your kid comfortable against the recommendation guide. What matters is to have the child comfortable. You may have to place the seat lower than recommended just for the sake of the child. However, do not make it too low so that the child suffers a backache when cruising using the bike.