1. I would like to know how many Sunah Rakah's are to be offered for Jumuah Prayer, growing up I prayed 2 rakah upon entering the mosque and after jamah salat i have prayed 2 rakah and then 2 again but I am unsure as to the significance of the sunah rakahs.
If you have already answered this question could you please guide me to the fatwa number?
2. What is the meaning of jazakallah and what is the difference between jazakallah and jazakamullah khairan.

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

The Prophet (Sallallahu Alaihi wa Sallam) said: "whoever makes Ghusl (ceremonial washing) and wears his best clothes, some perfume if he has any, then comes to the Friday prayer without stepping over other's necks to get to the front rows, then prays what Allah decreed for him to pray, then listens from the time the Imam starts the Khutba until he finishes it, his sins will be forgiven between this Friday prayer and the previous one." Reported by Abu Dawud.

As regards after Friday prayer, the Prophet (Sallallahu Alaihi wa Sallam) incited people to pray 4 raka'as after it as he (Sallallahu Alaihi wa Sallam) said: "Whoever wants to pray after Friday prayer, pray 4 raka'as." Reported by Muslim.

It is permissible for you also to pray 2 raka'as only after Jumua (Friday prayer). Muslim reported in his Sahih that Ibn Omar narrated that the Prophet (Sallallahu Alaihi wa Sallam) used to pray 2 rakaats after Jumua.

Therefore, we advise the questioner to continue to pray what he used to pray before and after Friday prayer.

With regard to the meaning of "Jazaka Allahu Khairan," it is a Dua from Allah to give good to a person in return of the good deeds that he had done.

The difference between "Jazaka" and "Jazakum" is that "Jazaka" is used for a singular person whereas "Jazakum" is used for plural.

Allah knows best.