When applying TurfGrassPro 18 - 3 - 6 50% SRN with Minors, children and pets should be out of the treatment area until the application has dried completely. Typically after 4-6 hours.
What fertilizer you need is going to vary depending on what nutrients are needed in the lawn throughout the year. We actually have a great guide that can explain how to select the best fertilizer for your lawn. You can find the guide here