There's no confusion here, but some lack of knowledge on your side.
In the congregation prayer there are some aspects one must be aware of: The imam leads the prayer and the ma'amums should follow him and in most cases the acts of the imam are sufficient for the ma'amums. This is the main difference between praying as a jama'ah (in congregation) and praying fadd (alone).
For many parts of the prayer this means either if the imam does something aloud it is no more necessary for you to do it, if he does it silently you should do it similarly.
For instance one difference between praying alone or following the imams that (according the majority view) the ma'amu's don't say any takbir aloud after the imam. And there's a difference of opinion on whether or not one should recite al-Fatihah with or after (both silently) or at all if the imam recites it loudly while listening to his recitation is agreed upon etc.
As for the prayers themselve you should know that prayers that are performed during the day time are known as sirri prayers (one prays them silently) while the prayers that are performed during the night time or at the edges of the day are known as jahri prayers (one prays them in normal or lightly loud voice).
To be more exact you recite al-Fatiha and the Surah or the verses of the qur'an which you've chosen to recite after al-Fatihah in an audible voice during the two first raka'as (only) of sobh/fajr (Fard), maghrib and 'Isha' prayer.
For further information refer to
How to be a proper Imam in a congregation of fardhu correctly? (Leading of Prayers) or How does one pray in congregation? and many other posts on the site.
