What are the dietary restrictions for Lent in Catholicism? There are some things that I've been told since I was kid that I'd like to ask about regarding fasting. I'm a of Catholic Maronite Rite and I'd like Catholic answers.

Are we allowed to eat whatever we want on Sundays? I've been taught not to fast on Sundays, therefore we can eat whatever we want on Sundays all day long.
Are we allowed to drink? I've been told that we can drink water, only Muslims don't drink water while fasting. Some Christians do it, but it's optional.
Is Saturday or Sunday the last day of lent? I believe it's Sunday, meaning you cannot eat on Holy Saturday, my friend is a Catholic too and he believes that he can eat on Holy Saturday.
What about fish and egg? I don't eat meat in the first and last week. however, I eat fish and eggs. Is it allowed? I've been told so.
I'm Catholic, but I don't know what a Maronit is.  One thing about fasting that people often forget is the reason we do it in the first place.  If you just do it because it is the rules, it will not benefit you at all.
Sundays and feast days are not actually part of Lent, so you don't have to fast.
I have not heard anything about not drinking water.
I would say if you go to the Easter vigil Mass, Lent is over when they turn the lights on.  (You would know what I mean if you have ever been to the Easter vigil Mass.)  If not, it is over on Easter Sunday.
I have never heard you can't eat meat the first and last week.  You can't eat meat of Fridays, though.  Fish is fine and I have never heard anything about not eating eggs.
Saying you will go to hell if you don't fast is just plain stupid.  Imagine if you get to heaven and God says, "You could go to heaven, except once 20 years ago, you didn't fast, so you instantly go to hell."  Even if it was a sin, just go to confession.  The only sin that is unforgivable is saying that God cannot forgive your sins.  He can, but you have a free will, so He won't forgive them if you tell Him he can't.