Regarding the abolition of slavery, Lincoln issued the Emancipation Proclamation in January 1, 1863, which declared all slaves in the Confederate states to be free. This declaration paved the way for the 13th Amendment, which abolished slavery throughout the United States, and was ratified in December 1865, after Lincoln's assassination.
Lincoln also promoted the Reconstruction Acts of 1867, which aimed to protect the rights of former slaves and to assist the South during this period of transition. This involved military occupation of the South and establishing state governments controlled by former slaves and Northern loyalists.
In terms of reunification, Lincoln aimed to rebuild and reunify the nation, and to avoid a long-term estrangement between the North and the South. His approach focused on healing the wounds of the war, reconciliation, and reintegrating the Southern states into the Union.
Lincoln aimed to create a post-war society based on equality, justice, and harmony. His goal was to bring the country back together, as a stronger union.