וְהַחֹנִים֙ קֵ֣דְמָה מִזְרָ֔חָה דֶּ֛גֶל מַחֲנֵ֥ה יְהוּדָ֖ה לְצִבְאֹתָ֑ם וְנָשִׂיא֙ לִבְנֵ֣י יְהוּדָ֔ה נַחְשׁ֖וֹן בֶּן־עַמִּינָדָֽב׃
在東邊、向日出之方紮營的，是猶大營的旗，按著他們的軍隊；猶大人的首領是亞米拿達的兒子拿順。
Rashi
קדמה means IN FRONT, which is expressed by קדם; and which side is it? The east side (מזרחה), and accordingly the west is termed אחור, the back side of the world (cf. Rashi on Exodus 27:13 and Note thereon).
Or HaChaim
והחנים קדמה מזרחה, "And the ones encamped in the east toward the sunrising, etc." The reason this verse commences with the conjunctive letter ו is that it follows the command to establish the camp around the Tabernacle and only proceeds to give additional details.
Chizkuni
והחונים קדמה מזרחה, “the ones who were encamped on the east side facing the sun;” they were facing the entrance of the Tabernacle as described at the end of Parshat T’rumah. (Exodus 27,13)