These three verses go together, rather than just verses 12 and 13. Nevertheless, they all cover the same concepts. The three gifts mentioned deal with the connections between the heavens and the heart. Miracles come from God, and Moroni has used the connection between a constant God and miracles to demonstrate that miracles continue if God continues (Mormon 9:15).
Through the gift of prophesy, the understanding of the heavens is delivered to one on earth.
The beholding, and the ministration of angels, are similarly blessings from heaven to one on earth. There is no indication that there is a particular person to whom these blessings come. While there is a single prophet for the whole of the church, all have the opportunity to have the gift of prophesy for their own sphere of responsibility. Similarly, there is no indication that it takes some special person to receive angels, only that the gift can be given (upon worthiness, certainly).