How do I perform Friday prayer if I miss praying with the Jamat, according to Qur'an and Sunnah?
Praise be to Allah, the Lord of the World; and blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
For your third question, know that it is unlawful to miss praying in congregation if you are able to attend the prayer - read Fatwa:83297.
This is for the prayer in congregation in general. No doubt, however, that attending the Friday prayer in congregation is an obligation on all Muslim men. And whoever neglects to attend it, commits a great sin as the Prophet said: "Whoever misses to pray three Friday prayers out of negligence, Allah puts a seal on his heart". [Reported by Ahmad]
Allah knows best.
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