As'Salaam'o'Aliekum dear brother,
If a person who kills someone purposely or by accident and pays the blood money to the family of the deceased, is one required to do any other things like fasting, freeing a believing slave etc or has he now been pardoned by Allah?
Wallaikum As Salaam!
Inshallah the below verse should answer your question!
No believer shall kill another believer, unless it is an accident. If one kills a believer by accident, he shall atone by freeing a believing slave, and paying a compensation to the victim's family, unless they forfeit such a compensation as a charity. If the victim belonged to people who are at war with you, though he was a believer, you shall atone by freeing a believing slave. If he belonged to people with whom you have signed a peace treaty, you shall pay the compensation in addition to freeing a believing slave. If you cannot find* a slave to free, you shall atone by fasting two consecutive months, in order to be redeemed by God. God is Knower, Most Wise.
May the Almighty Allah have mercy on us to forgive our sins and guide us all to the true path of
Islam as per the Koran for rest of our lives.