くれます is also a verb for "giving". It is used to state "somebody gives me(or us) something", the giver being the subject of the sentence. On the other hand, あげます, another verb for giving which was introduced in Structure 1, cannot be used when the indirect object(i.e., the receiver) is first person. In a question which asks about someone's giving something to the person spoken to(i.e., あなた[you]), the verb くれます is used: Xさんは あなたに Nを くれますか(Will X give N to you?).
X gave Y a present.
X gave me a present.
Did X give you a present?
When the receiver is someone whom the speaker considers a member of his/her "in-group", that person can be presented as the indirect object of the verb くれます, as in いもうとに くれます(S/he gives it to my younger sister) and ともだちに くれます(S/he gives it to my friend).
マナさんは わたしに じしょを くれました。
Mana gave me a dictionary.
A: マナさんは あなたに なにを くれましたか。
What did Mana give you?
B: わたしに ほんを くれました。
He gave me a book.
山田さんは いもうとに おかしを くれました。
Mr./Ms. Yamada gave some sweets to my younger sister.
田中さんは わたしの クラスの マリアさんに おかしを くれました。
Mr./Ms. Tanaka gave some sweets to my classmate Maria.
Both あげます and くれます mean "to give" in English. Whether the receiver is わたし(たち)or someone else determines which verb should be used. It should also be noted that the speaker's focus is on the giver(i.e., the subject of the sentence in this case) when s/he uses あげます. On the other hand, when the speaker uses くれます, his/her focus is on the receiver, who is the speaker himself/herself or someone the speaker empathizes with.