This is a courteous way to describe someone else's action. You use it when the person you're talking about deserves respect—like your boss, a teacher, a customer, or an elder. It is a set pattern: you take the verb's ます-stem (the part before ます), put お in front, and になる after. For example, 話す becomes お話しになる, 帰る becomes お帰りになる. The subject's action is the one being honored, so you would never use it about yourself or your own in-group.

This pattern is common in polite conversation and customer service. It is a bit more formal than plain verbs, but not stuffy. You'll hear it in shops, offices, and everyday respectful talk. It works with many verbs, but for some common verbs like 食べる and 見る, there are special honorific forms (召し上がる, ご覧になる) that you'll learn later. Use this pattern when you want to elevate the other person's action.

In terms of register, it is polite and respectful, used in both speech and writing when addressing someone superior. It's not rude or too literary—it's standard honorific language.