Did John Proctor die in the end of the play?

Yes, John Proctor is hanged in the play's final scene. On the day of his scheduled execution, John is urged to confess to save himself from hanging. With two children and a pregnant wife, Proctor has plenty of reasons to continue living. He is in his thirties and would likely have a long life ahead of him.
Proctor briefly considers giving a false confession so that he might live. But he realizes that in doing so he would be setting a negative example for his children, and he would lose the respect of people that matter to him. As a Puritan, he would also be concerned that in telling a lie that amounts to renouncing God, he would be eternally damned.
The authorities want John Proctor to confess because they think it would lend the trials more legitimacy. There is growing public renunciation of the trials because pillars of the community stand accused, like Rebecca Nurse, and the admission of spectral evidence is creating significant doubt. However, John Proctor will not allow himself to be used as a political tool of the theocracy, and so he chooses execution over giving a false confession.

Yes, John Proctor is hanged at the end of the play. In act 3, John Proctor travels to Salem with Mary Warren in an attempt to expose Abigail Williams as a liar and put an end to the unjust, corrupt witch trials. Unfortunately, John Proctor ruins his reputation by admitting that he had an affair with Abigail Williams and is arrested for challenging Salem's court officials. In act 4, John Proctor is in prison and struggles with the decision to offer a false confession, in order to save his life, or accept dying by refusing to admit to witchcraft. After John Proctor initially signs his false confession, he experiences a change of heart and rips up his confession in front of the court officials. John Proctor finds redemption by retaining his integrity and refusing to falsely confess to being involved in witchcraft, in hopes of undermining the court's authority and ending the witch trials. The play ends as John Proctor is led to the gallows, where he dies a martyr.