Is congregational prayer obligatory for a medical student residing in Germany, for whom the mosque is 20 minutes away by train, there is no Adhan (call to prayer), and who faces academic pressure?

Congregational prayer in the mosque has immense reward and is one of the greatest means of steadfastness in obedience. It is obligatory only for those who hear the call (adhan (definition)) without a loudspeaker when sounds are quiet. This is indicated by the Prophet's (peace be upon him) hadith (definition) to Ibn Umm Maktum, as well as the words of scholars such as Ibn Hajar and Al-Uthaymeen. So, if the distance between you and the mosque prevents you from hearing the usual adhan, you are not obliged to go to the mosque for the five daily prayers, with the exception of Friday prayer.