Why "from" is used here not "with"?
Native speaker’s answer
Rebecca
"Across from" is a phrase that means "opposite of". When referring to someone or something being opposite of someone or something else, "across from" is the proper phrase to use. "With" is generally not used after the word "across". Here are some examples using "across from": Ex: She was sitting in a chair across from me. Ex: I work across from a bakery.