We are having a friendly debate can you please help me with the following questions and the reference’s must be authentic Sunni books, Quran and No Shia books please.

Questions:-

1) If are fore fathers are Sunni Syed why didn’t they come out to say they are Shia later if they were doing taqqiya?

2) In the Quran it says we should stay with the truth and trust Allah swt so why are the descendants of the Ahlalbayt doing taqqiya when they’ve got Allah swt on there side especially if they are wali Allah and Fakir.

3) The Sabah of the Sunni why ain’t they the rightful heirs after the prophet saw passed away and when the Sabah appointed themselves to be the caliph’s why didn’t imam Ali (as) protest against them or picked up his sword towards them.

4) If the sabah’s are bad people why are they buried next to the prophet saw? Wouldn’t the earth sallow them up by the permission of Allah swt for disrespecting the prophet saw and the Ahlalbayt?

5) How do you know that Shia fiqh is the true fiqh it could be a cult?

6) Why did Imam Ali (as) reject caliphate? Why did he become the 4th caliph?

If you can answer these with Sunni references authentic up to date that will help me in my debate.

There are more questions but we are only starting on these. Once you’ve answered these questions InshaAllah I will forward the rest questions.