This is Afterlife Quest: Theodore Saga. Book 1 (Complete), Book 2 (Complete), and Book 3 (In Progress)
Book 1: The Denial of Theodore
https://www.royalroad.com/amazon/B09WZKRVXP
Theodore is a young man taken from this world too soon. He is in the first stage of grief over his own death, but he is fighting this truth as much as he is fighting the monsters that populate his current plane of existence. Where is he exactly? Why is he here? Will he gain the required skills and grow strong enough to stay "alive"?
Book 2: The Stain of Guilt
https://www.royalroad.com/amazon/B0BF4DR95Y
Theodore continues his journey after many triumphs and foibles. He is dealing with the guilt of leaving his beloved behind after the choice he made.
Book 3: Raging on the Sea
Theodore is having to bring peace to the North Sea. Is that all he is attempting to bring peace to?
This is a LitRPG Lite set in the afterlife. Follow Theodore as he adventures in the great beyond.