She spends three dollars a day on lunch and dinner.
Literal
She [topic-は] lunch and dinner [on-に] every-day three-dollars uses.
昼食と夕食に lists two meals with the exhaustive と ('and'). 毎日 ('every day') is the frequency adverb. ３ドル uses the counter ドル for dollars — this sentence originates from an English-language context. 使う ('to use/spend') is the standard verb for spending money.