Welcome to the wonderful world of tegus!!!
They are very addicting. Bert and Hester typically supply their tegus with an instruction sheet and are very helpful with any questions you
may have down the road, or people here are super firendly too! 
Babies can be fed crickets, some mealworms, ground turkey, cooked (boiled)chicken. All must have supplements (Calcium / Vit. D3) added daily, then the supplements can be cut back to every other day or so once they are approx 1 to 1-1/2 yrs. of age. Babies will eat about 90% meat, crickets and will only eat veggies and fruit when older as you saw in Bert's pic. Babies can be fed 2-3 days per day and feed them as much as they will eat. If crickets, most will eat a dozen per feeding. You can mix some crickets and meat as well to provide a variety. Some people also supply thawed frozen pinkies too, but also need supplement for they do not have too many
nutrients required by tegus.
The best of luck and keep us posted! Even a pic would be great when he/she arrives.
Greg