1) What is the ruling on praying jummuah Friday prayers behind a sunni imam. Would my jummuah suffice for my dhuhr or would I have to repeat my salah as dhuhr?

2) What is the ruling on jummuahs as well? Is it obligatory every Friday or is it optional in the occultation of the imam.

by

1) Dhuhr must be done with the niyyat of wajib

2) Either Dhuhr or Jumuah is wajib on Friday. This is the famous opinion of the fuqaha during the time of ghaybah.
Even during previous Imams time there is no record of any of our Imams having led Jumuah except Imam Ali