In order to just add simple calories and the name of food as well as the macros, we recommend using this function.

In the Diary tap "+" to add food for a meal and then choose the meal you would like to track. On the next page, please click on the three little dots top right hand and on Quick track.
Simply add the amount of calories you had and a short description of the food item, add the macros and click on Track.  (Please note: each field has a maximum limit of 5 characters and does not support decimals)