[Calderyon]

Do they have time to discuss things in between the votes?

Excluding twists, I would say usually 6 hours to half a day.

How long does tribe vs. tribe vs. tribe last?

Depends. If they are planning a tribe shuffle (dismantling the tribes and creating them again), 3 more eliminations. With or without it, at least 1 elimination, since they usually want the numbers to be even when they go back to the 2 tribe system meaning they randomly draw rocks or color bullet thingys or do a schoolyard pick and determine the rosters of two new tribes, meaning three tribes will become two.

How do the competitions work when that ends?

Two tribes battle against each other for rewards and/or immunity. The winner gets a reward/win immunity and the losers lose reward/lose immunity and have to go to the tribal council to vote someone out.

The tribes usually merge (become one tribe) when 9-12 contestants are left in the game.
After that you win and lose the rewards (the winner however can bring 1-3 people along with him/her to enjoy the reward) and immunities individually.

I know Survivor has a jury too but how does it compare to the BB one / how many are in it?

Not much difference, except the questioning is a longer and there are three instead of two to question.

After the jury stage begins, and the jurors begin to get voted of, The jurors go to a Ponderosa, a production camp complex, which is located somewhere in the same region. After they have come to terms with the loss and themselves after the competition, they get weighed, then they get escorted to their rooms where they can clean themselves and rest afterwards. Then they eat, talk with crew or talk/fight the other jurors and then hang out and rest until it´s time to go and attend the next tribal.

In Survivor, the jury members attend every tribal after the jury stage has begun and "gather information" for the final tribal.

I've heard a lot about the immunity idol(s) but how many in a season and how exactly do they work?

I know it basically saves them but then what happens after that if they were supposed to go.. next highest number of votes is out?

Since they were introduced usually 2-4 per season at the start and one on each camp. Usual rule is when an idol is being used it gets a new one gets hidden for someone else (very often nowadays it´s the same guy/girl though)

When you find an idol, you can make yourself or somebody you want immune, before the votes are announced. (There has however been an idol that made it possible to make yourself or someone else immune ie: null your votes after the votes were announced.)

You´re correct, if you succeed in using the idol, ie: you predicted correctly that you were the target and got the most amount of votes, the next one with highest amount of votes gets voted out.