すみません、その文法は英語だけで説明することができます。 For your first question, the the one that uses を is correct. が is a subject marker, so if you used that instead, it means that the information is the thing that is conveying or telling something in a physical manner. When を, an object marker, is used, it means that the information is the thing that is being conveyed. For your second question, 電話をかける is correct for the same reason as the first question. When you use を, it means "to give somebody a call" or "to call somebody." If が were to be used, it wouldn't make sense because the phone would be the thing calling someone up, not you. That's the best I could approximate the sentence, if it said that.