Taubah and Repentance

Q: If someone says "Astaghfirullah alladhi la ilaaha illa huwal hayyul qayyum wa atubu ilayhi" 3 times, Allah will forgive all his sins. Does that include major sins?

Q: A person committed some mistake but alhmdullilah, Allah saved him from getting into a big mess. He thanked Allah but he gets thoughts that if he had avoided the mistake, things would have been different, etc. and dwells on his past. He always did some mistakes because of laziness or ignorance but Allah saved him. So, how should he thank Allah but not think of the mistake?

Q: I used to produce music and instrumentals but alhamdulillah I have repented from both listening to and making music. I am worried about the songs I released before, should I worry about them and try to get them deleted or am I free from it since I repented?

I also produced the background music for a podcast/show. I have sincerely repented from making any more music or sending/promoting my music. I feel absolutely horrible and I hope that this spread of my music doesn't come for me in my grave.

Q: I would like to ask the following question on repentance

1. Does repentance wipe out previous sins?

2. Am I always obliged to confess to the one whom I've wronged even if this might bring severe enmity?

3. How do I feel regret during repenting?

Q: What is the ruling if a person seeks istighfaar sincerely everyday but does not quit the sin?

Q: If we backbite people, will we ever enter paradise if we did not apologize to the people but repented to Allah for the people to forgive us for backbiting?

Q: How does one repent from insulting the Sahaabah? 

Q: If a person makes kufr by calling an average human being the son of god, how should he repent?

Q: If anyone commits adultery or fahashi with someone else's wife, but not sexual intercourse, how does he ask repent to Allah for this sin? Is this huqooq ul ibaad or not?

Q: I made thread bracelets for a school project and my family. Since we’re from the subcontinent, amulets are common.

Some of my cousins asked for bracelets and I made them for their children to wear. I made for others but some of those people have moved out of the country and I am no longer in contact with them.

Also I had wandered into astrology and zodiac signs and stuff, discussing it with those around me including my classmates of which some are kaafirs and some Muslims. I did not know these were acts of shirk and most lasted from before to mid puberty. I don't know what to do so I can give charity on their behalf even if they are kaafirs since I'm not in touch with them.

Before I rarely prayed and fasted but now I know alhamdulillah I’m more practicing and have realized that the shirk I have spread. Is there a way to resolve the issue? I have no idea of their intentions and some are requesting bracelets but what should I say.