Thank you very much for your question. It is our pleasure to answer it.

In the name of Allah, We praise Him, seek His help and ask for His forgiveness. Whoever Allah guides none can misguide, and whoever He allows to fall astray, none can guide them aright.

Dear brother, reciting out loud in the prayers in which the Prophet (peace be upon him) recited out loud, and silently in the prayers in which he recited silently, is one of the Sunnahs of prayer, not one of the obligatory duties. But it is better for the worshipper not to go against the Sunnah of the Prophet (peace be upon him).

We do that following the example of the Prophet (peace be upon him). We recite silently in the prayers in which he recited silently, and we recite out loud in the prayers in which he recited out loud, because Allaah says (interpretation of the meaning):

"Indeed in the Messenger of Allaah (Muhammad) you have a good example to follow” (Surah Al-Ahzaab: 21)

And the Prophet (peace be upon him) said: “Pray as you have seen me praying.” (Al-Bukhaari) 

And Allah Knows best.