
Ladder of Divine Ascent icon, St. Catherine’s Monastery, Sinai, Egypt
Heaven is the state of existence we as believers wish to enter into in after our bodily life and death. Also known as eternal paradise, it is the culmination of our divinization, the ultimate end and fulfillment of the deepest human longings, the state of supreme, definitive happiness (CCC 1024).
And there will be no more night; they need no light of lamp or sun, for the Lord God will be their light, and they will reign forever and ever. (Rev 22:5)

Illustration of Hell from the Hortus delicarium by Herrad of Landsberg
Hell is eternal fiery punishment for refusing to love God and the consequence of dying in mortal sin without repenting and accepting God’s merciful love. It is a place or state of torment where we remain separated from Him for ever by our own free choice (CCC 1033).
Depart from me, you who are cursed, into the eternal fire prepared for the devil and his angels. For I was hungry and you gave me nothing to eat, I was thirsty and you gave me nothing to drink, I was a stranger and you did not invite me in, I needed clothes and you did not clothe me, I was sick and in prison and you did not look after me. …whatever you did not do for one of the least of these, you did not do for me. (Mat 25:41-43)
This Catholic Plan of Salvation sums up the LAST FOUR THINGS very nicely. Start at ‘Begin Here’ at the bottom left and follow the arrows (rather than the numbers).
May God’s peace and eternal salvation be with you.