Assuming that the underlined word is eated, I must say that the best replacement for it is ATE.
Ate is the past form of the verb eat. As it is stated that the action took place "yesterday" and yesterday refers to the past tense, the main verb has to be conjugated in its past form.
"Eat" is an irregular verb, that is why eated is wrong. It is not a word.
Irregular verbs are verbs that don’t take on the regular –d, -ed, or -ied spelling patterns of the past simple or past participle.
