Praying Salat al-Fard in the mosque! My mosque is a 15 minute walk from my house, but near my house there is clinic of doctors and they have Musalla that they pray only three prays Jamaah (together), so can I pray with them in the Musalla or to go to the mosque? Can I pray Salat al-Fajr and Isha at home with my family or with friends?

Praise be to Allah, the Lord of the World; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

Basically, the prayer should be performed in the Mosque where the Azan is proclaimed for all prayers. It is proved in Sahih Muslim that Ibn Masoud (Radiya Allahu Anhu) said: "Whoever likes to meet Allah a (true) Muslim, should keep on performing the (five) daily prayers where they are called for (i.e. in the Mosque)" .
However, if it becomes impossible to perform the prayers at the Mosque because it is far, then you can perform them at the nearest Musalla (a place of prayer) even for two or three times. This, in fact, is better than performing the obligatory prayers at home.
In addition, there is no harm to perform the Isha and Fajr prayers in congregation with your family at home as long as it is unfeasible to go to Mosque or Musalla.
Allah knows best.