Do your best
Your child will not starve
Get a variety of foods over the course of a week
Food preferences change quickly at this age, keep introducing foods even if they don't like them at first.
OK, now we can get to the technical stuff.
Children ages 3 through 5 years old generally need about 1200 to 1800 calories a day, but those who are very active may need as many as 2000 calories.¹ They can meet their basic nutritional needs by eating the types and amounts of foods listed below each day. The lower end of the range provides 1200 calories, the higher end provides 1800 calories. These are general guidelines only.