No you shouldn't mainly because it is not in your scope of practice. there will be legal consequences if you are caught and you are not licensed to administer medication
Anyone who falls between the 5th percentile and the 85th percentile is a healthy weight. If someone is at or above the 85th percentile line on the chart (but less than the 95th percentile) is overweight.
In some cases yes. Kids tend to learn faster than the average toddler.
Using your phone while driving