I don't understand what happened?

Rating: 3/10 (11 March 2019)

As English is not my native language, I might miss something in the film. But in general, I can't understand this story.
First, I don't know why they have to talk about Carol's past (when she was small and was hated by her strict father), and don't know how it added up to her character, the scene that one another pilot told her that she's a good pilot but she is so emotional doesn't link to anything later on. I don't even know why we need to see her past.
Second, the character is described as emotional and struggling with emotions and memories, but all the whole film she has no connection with anyone. She admires Dr Marvell, who no major impact to her has been showed. Carol didn't even know who Dr Marvell really was, what she was working on, who she interacted with, what was her belief and why she protected Skrull till the time Marvell killed herself (and also she knows that she might kill Carol but she just couldn't even say Sorry).
Carol doesn't have any connection withYon-Rogg even they've been through 6 yrs together, he transfered part of his blood to her. Also Carol doesn't have any connection with the rest of the Kree team. And she described herself as "emotional".
Third, there's no reason that she choose Skrull over Kree. Both of them don't show any threat to Earth (where she really needs to protect). She spent 6 years with Kree, considered them as heroes, and she changed in one minute because she believes in Marvell (the one she knows nothing about).
Fourth and the last thing, there's no turning point showing in the film, where a normal human being received a super power super power, there's no struggle in receiving both the power and the responsibility, she like was born to be a strongest in the galaxy, not born as a soft woman. And Carol has the face of a people without any struggling in life.
And add on it, there's no twist which is really twisted, Jude Law? Always a bad guy. The cat? There must be something special about it.