Im using an Anki deck to study vocabulary. It's translation for the sentence 私が手伝いましょう is "Can I help you?". Im a bit confused, as I see no question marker in that sentence. I would guess it's meaning to be "I (We?) will help you (us?)". I'm a bit confused since the sentence starts with 私が but ends with ましょう。Is this a common phrase or is the translation incorrect? I would appreciate any help in breaking down this sentence.