You had better not meet with someone who won't tell you their company's name or their school's name.
You shouldn't meet with someone who won't tell you where they work or where they go to school.
ご質問ありがとうございます。
「自分の会社名とか学校名教えない奴と会わない方がいいよ」は英語で言いますと「You shouldn't meet with someone who won't tell you their company's name or their school's name.」や「You shouldn't meet with someone who won't tell you where they work or where they go to school.」になると思います。
「会社名」は「Company's name」や「Where they work」と言えます。
「学校名」は「school's name」や「where they go to school」と言います。
「会わない方がいい」は「You had better not meet」か「You shouldn't meet 」と言います。
「教えない」は「won't tell you」と訳しました。
役に立てば幸いです。