YOU SAID:

I am going to eat dinner after I do the dishes.

INTO JAPANESE

私は料理をした後に夕食を食べるつもりです。

BACK INTO ENGLISH

I'm going to eat dinner after cooking.

INTO JAPANESE

私は料理を食べた後に夕食を食べるつもりです。

BACK INTO ENGLISH

I'm going to eat dinner after I eat the food.

INTO JAPANESE

食べ物を食べたら夕食を食べるつもりです。

BACK INTO ENGLISH

I'm going to eat dinner when I eat food.

INTO JAPANESE

食べ物を食べる時に夕食を食べるつもりです。

BACK INTO ENGLISH

I'm going to eat dinner when I eat food.