These skills are of course a very important part of the child development and any weaknesses detected will usually be seen through the inability of the child’s capability to eat by themselves, write legibly or to perform other simple tasks such as page turning and personal grooming tasks.
Here too there should not be too much concern if the child does not develop such skill as other in the same age group would have already been able to do so. There would only be a need to consult a medical professional if the progress to this level takes an unusually longer time frame than the norm.