A juz is one of the 30 parts of the Quran. Reading by juz is a way to move through the whole book without choosing a surah first.
Open a part
Each juz page uses the same Arabic and Bangla lines as a surah page, and the same play buttons. Juz 30 holds the short surahs at the end of the Quran. Juz 1 starts at Al-Fatiha.
If you would rather pick a chapter by name, the surah list is the other way in.