What if someone who is sinner all his/her life and then decides to repent days or hours before his death.Will he/she go to paradise?

Answer 1

Whosoever shall call upon the name of the Lord shall be saved. Think of the thief on the cross when Jesus died. He was literally being executed for his crimes, yet he believed on Jesus and was able to god to heaven.

Answer 2

Yes that person will enter paradise if their repentance is genuine and they no longer trust in their own goodness to save themselves. We know this from two passages mainly: the parable of the eleventh hour worker in Matthew 20:1-16 and Luke 23:39-43. In the first passage, Jesus makes it clear through the workers in the vineyard that each will receive the same wage (that wage being salvation) regardless of the length of their labor. In the second passage, Jesus demonstrates the truth of the parable by stating clearly that the criminal who was crucified alongside Him would enter paradise based on his defense of Jesus' righteousness; a clear sign that the man did not trust in his own and knew that he needed Jesus' righteousness to survive the judgment coming at his imminent death. I have known many who have sincerely repented at "the 11th hour" of their lives. It is good to know that we can trust Christ's mercy and God's justice displayed on the cross.