Ibn ‘Abbās (may Allah be pleased with him and his father) reported that the Prophet (ﷺ) said: "We are the last of the nations, and the first to be brought to account. It will be said: Where is the unlettered nation and its Prophet? Thus, we are the last (in time) but the first (on the Day of Judgment)."
The Prophet (ﷺ) informed that his nation is the last of all nations in existence and time, yet it will be the first to be called to account on the Day of Judgment. On that day, it will be said: Where is the unlettered nation and its Prophet?—in attribution to the Prophet's unlettered nature, as he neither read nor wrote. They will be called first to account—thus, we are the last in time and existence, yet the first to be brought to account on the Day of Judgment and the first to enter Paradise.