These thematic pictures of खाना are analogous to a visual dictionary. The theme "खाना" is split into several parts. For children, especially toddlers from 1 to 5 years old, it is better to divide the sets of cards over several days, or even weeks, so that the information is absorbed better. This is especially true if you are using flashcards to learn hindi language that is not your native language.
To expand your hindi language vocabulary on the "खाना" topic, flashcards games are the best way:
make memory with "खाना"
assemble puzzle with खाना
make a memory chain or group images by color, size or other attributes