KJV:

1 Then he brought me forth into the utter court, the way toward the north: and he brought me into the chamber that was over against the separate place, and which was before the building toward the north.
2 Before the length of an hundred cubits was the north door, and the breadth was fifty cubits.

NASB:

1 Then he brought me out into the outer court, the way toward the north; and he brought me to the chamber which was opposite the separate area and opposite the building toward the north.
2 Along the length, which was a hundred cubits, was the north door; the width was fifty cubits.

‫א  וַיּוֹצִאֵנִי, אֶל-הֶחָצֵר הַחִיצוֹנָה--הַדֶּרֶךְ, דֶּרֶךְ הַצָּפוֹן; וַיְבִאֵנִי אֶל-הַלִּשְׁכָּה, אֲשֶׁר נֶגֶד הַגִּזְרָה וַאֲשֶׁר-נֶגֶד הַבִּנְיָן--אֶל-הַצָּפוֹן.

‫ב  אֶל-פְּנֵי-אֹרֶךְ אַמּוֹת הַמֵּאָה, פֶּתַח הַצָּפוֹן; וְהָרֹחַב, חֲמִשִּׁים אַמּוֹת.

First of all, at the end of the first verse, "north" should be separated by a comma, because "the north" does not refer to the building (the external building of the Temple, where the storerooms are located), but to the chamber, which is located near the way toward the north.

A place that has a length of 100 cubits and a width of 50 cubits is located in the outer court, on the pavement, which is near the outer wall. This place is fenced off from the rest of the outer court, but the fence has a formal character: a sagging chain hanging on metal posts. These three buildings located on this fenced off site are designed for Levites: two buildings are halls where the Levites have lunch, and the building closest to the inner court is a working locker room for Levites who perform work that requires special clothing.

Due to the fact that the size of this fenced place in the outer court is indicated in Ezekiel's prophecy, we know that the width of each of the 30 buildings on the pavement is 30 cubits: three buildings can be placed at 100 cubits of length if their length does not exceed 30 cubits (we must consider the minimum interval between buildings).

The northern doors are the service entrance to the inner court. This service entrance is used by the Kohanim, as well as singers and other Levites serving on on the outer part of the inner court.

The chambers themselves, to which the angel led the prophet, are buildings intended for the Kohanim. In this building, located in the north-west of the inner court, on the outside on the ground floor there are refrigerators for the Kohanim's share of the meat of peaceful sacrifices; on the inner side is a kitchen where they prepare the meat of sacred sacrifices that only Kohanim can eat; on the second floor there are pantries where sacred clothes for the Kohanim are stored; on the third floor there is a hall where the Kohanim can relax and, if necessary, can hold their working meetings.