Jacob and Esau: what is this story all about? This is how I see the story of Jacob and Esau (Genesis 25 and 26):

They are two very different twins who seem to fight a lot. Esau goes hunting and he is starving when he gets back. He asks Jacob for some stew. Jacob replied, "First sell me your birthright." "Look, I am about to die," Esau said. "What good is the birthright to me?" So Esau accepts the trade and it says "he despised his birthright."

1) When Esau says he is about to die, is this figuratively (from hunger) or literally he thinks he is close to dying from old age?

Then it gets kinda weird because Isaac's wife, Rebekah, tells her son, Jacob, to trick Isaac into thinking he is Esau and give the blessing to him. Jacob is hesitant and says "I would appear to be tricking him and would bring down a curse on myself rather than a blessing." But then she says, "Let the curse fall on me. Just do what I say." Jacob then lies and tricks his father into believe he is Esau so Isaac blesses him.

2) Isn't Rebekah promoting lying, deception, and disrespecting elders?

3) What is the difference between birthright and blessing? They sound similar.

4) If they are similar, why didn't Jacob just tell his father that Esau willingly gave up his birthright?

5) Are Isaac's words/blessings/curses really powerful enough to change the course of Jacob/Esau's life?

Sorry for all the questions but this whole passage seems really confusing to me.
I think that the lesson learned here is essentially the same one as the parenthood dispute in King Solomon's court: regardless of who the blessing actually originally belonged to by birth, it ended up going to the one who could truly appreciate its worth.

We have here the story of Jacob, a man of spiritual sensitivity, contrasted with his brother Esau, who was a hunter.  Hunters are not well-regarded in the Old Testament, (the archetype being Nimrod, the "mighty hunter" who is traditionally equated with the founder of Babylon and the one who directed the construction of the Tower of Babel, and standing in opposition to God and his people,) and we see Esau following the stereotype, caring more for temporal things than for the things of God.

Where his character really shows is in the matter of the birthright.  This was the continuation of the great covenant blessing, given by God to Abraham and then passed down to Isaac, to have a numberless posterity and be the father of many nations, (see Genesis 15 and 17) and, most impressive of all, that "in thy seed shall all the nations of the earth be blessed," (Genesis 22:18) which was literally fulfilled by Christ being born through his lineage.

Jacob appreciated these blessings, whereas Esau--who is by this point a grown man able to go out on hunts alone and look after himself--comes across as a petulant child.  You can almost hear the whiny tone in his voice as he says, "who cares about the stupid birthright? I'm starving!" All he cared about in the moment was the needs of the moment, and for that he was willing to sacrifice great eternal blessings.

Unfortunately, for whatever reason, Esau was his father's favorite.  And as the transaction had occurred between Jacob and Esau in private, with no witnesses, if Jacob were to claim that Esau had sold him the birthright, it would be his word against his brother's.  And as we see from subsequent events, Esau had every intention of taking the birthright that was no longer his, even if it be by force.  Bear in mind, when asking why Jacob used deception to obtain the blessing that was rightfully his, that Esau was willing to use deception (claiming that he was still entitled to it) and worse to obtain it when it was not rightfully his.

As for Isaac's words being powerful enough to change the course of his sons' lives, bear in mind that they aren't ordinary words in this case. They're carrying the weight of a covenant established with the Lord, and the Lord does have the power to change the course of people's lives.