You will need to reach out and speak to the Blacksmith. You will come across this person in the second main mission of the game’s story mode. Once you have engaged her in a conversation, you can buy items from her through the world map. One of these items is the Book of Reincarnation, which is available at the cost of 10,000 currency.
For a player who has just started the game, it might be a bit too expensive an item to attain, so you will need to play through several missions till you reach the desired funds. Once you have obtained the Book, it can be used from your inventory to rebuild the stats of your character.