The child must decide how much to eat

The basic approach is that the parent decides what, where and when to eat, while the child decides how much to eat. During this period, the child should be placed on the table, the feeder should be an example to the child by eating his food with pleasure, and the child should not have difficulty while not eating.

https://www.bbcgoodfood.com/howto/guide/carlos-gonzalos-my-child-wont-eat