God has a book of life,and for your name to be written in it requires the acceptance of Jesus Christ,His only begotten Son,and righteous living.
And the Lord said to Moses, “Whoever has sinned against Me, I will blot him out of My book.{Exodus 32:33}.
And I saw the dead, small and great, standing before God, and books were opened. And another book was opened, which is the  Book of Life. And the dead were judged according to their works, by the things which were written in the books. The sea gave up the dead who were in it, and Death and Hades delivered up the dead who were in them. And they were judged, each one according to his works. Then Death and Hades were cast into the lake of fire. This is the second death. And anyone not found written in the Book of Life was cast into the lake of fire “[Revelation 20:12-15].
Jesus told His disciples, that when your name is written in the book of life,that’s a good reason to rejoice:
“Nevertheless do not rejoice in this, that the spirits are subject to you, but rather rejoice because your names are written in heaven.”
{Luke 10:20}
Remember therefore how you have received and heard; hold fast and repent. Therefore if you will not watch, I will come upon you as a thief, and you will not know what hour I will come upon you. You have a few names even in Sardis who have not defiled their garments; and they shall walk with Me in white, for they are worthy. He who overcomes shall be clothed in white garments, and I will not blot out his name from the Book of Life; but I will confess his name before My Father and before His angels.
(Revelation 3:3-5 )
But there shall by no means enter it anything that defiles, or causes an abomination or a lie, but only those who are written in the Lamb’s Book of Life.
(Revelation 21:27)
If you didn’t accept God’s only begotten Son,then your name is not written in the Lambs book of life,to be written in the book,just go to the top of this blog,click onto the salvation page, and follow the instructions, then allow the Holy Spirit to lead and guide you for the rest of your life.