I'm not really sure specifically what the 'Hamdel Thor' back story is as it's not a widely known common tale. It could be a very specific or personal story, or perhaps a name that's not familiar in mainstream stories.
The back story in the Thor Ragnarok trailer shows that Thor is facing a great threat to Asgard. Hela, the goddess of death, has emerged and is bent on destruction. Thor has been away and returns to find his world in chaos. He has to fight not only Hela but also deal with being stranded on the planet Sakaar. This sets the stage for an epic battle to save Asgard and its people.
Well, Thor's back story is quite fascinating. He hails from Asgard, a realm of the gods. His father, Odin, is the All - Father. Thor was raised among the other gods and goddesses. He was trained in combat from a young age. His role in Norse mythology is to defend Asgard from various threats, especially those posed by the giants. He has a hot - tempered nature, which sometimes gets him into trouble, but his heart is always in the right place. His relationship with his hammer Mjolnir is central to his identity, as it gives him the power to fly and control the elements. For example, when the giants try to invade Asgard, Thor is often the first to rise up and fight them with his hammer in hand, unleashing bolts of lightning to drive them back.
The back story of Thor Love and Thunder is complex. Thor has been on a continuous journey of self - discovery. His time with the Guardians of the Galaxy is part of it too. He has seen different cultures and faced various threats. When it comes to Jane Foster, she is battling cancer. Her connection to Thor and her transformation into Mighty Thor is a key aspect. This is all set against the backdrop of a universe where the gods are being hunted by Gorr. Thor has to step up once again, not just as a hero, but also as someone dealing with his past and his love for Jane.
Loki, Thor's brother, has a complex back story. He was adopted by Odin after being found as a baby in Jotunheim. Loki always felt like an outsider in Asgard. He was envious of Thor's popularity and position as heir. His discovery of his true Jotun heritage further complicated things, leading him to have a sense of betrayal and a thirst for power which often put him at odds with Thor and the rest of Asgard.
In many cases, Thor eventually regains Mjolnir. However, the circumstances and challenges he faces to do so vary greatly from one comic series to another.
Well, Valkyrie in Thor: Ragnarok has a really interesting back story. She used to be a Valkyrie, which was like a super - important and powerful role in Asgard. When Hela showed up and basically wiped out most of the Valkyries, Valkyrie was left with a lot of trauma. She escaped and ended up on Sakaar. There, she became a bit of a loner, working for the Grandmaster. But deep down, she still had that Asgardian warrior in her, which Thor was able to bring back out.