Watched it

How can you just start now the F&F series when its 20 years old now?

You see Jason Statham as Deckard inside his flat or what and he had a guy inside a punching bag and closes it and opens his door and sees Han

Its a plot hole

At the start of the movie, it's revealed that Mr. Nobody had captured Cipher and a rogue agent who happened to be Jakob took down his plane when delivering her and he and Otto captured her.
She spends most of her time inside a glass box manipulating Jakob and Otto, Jakob's partner and snobby rich prick who's father is a minister of a Foreign country. But Her magnet plane is a simulation or something.

I do believe it was a rhetorical question on the OP's part. Even though her character has a connection to a previously seen character, she serves no purpose, except to continue the franchise's history of having an appearance by a hip-hop artist.

-Neela isn't mentioned or referenced

-Han appears after the second half afterwards he's in almost every scene following that.

-She gets to do a fair bit of action, the fight in Tokyo with Letty and the henchmen and she's involved in the last action sequence in Tbilisi.

Han's story between "Fast 6" and "Furious 7" goes like this:
After Gisele's death, Han was aimless, because he had no idea what to do without her, so one day Mr. Nobody, who used to work for the CIA and worked with Gisele in the past, visited Han to offer him a job in Tokyo to steal some tech which was known as Project Aries from a scientist couple, but then when the couple and their daughter were leaving, the couple were killed but Han manages to save their daughter Elle, by killing the thugs and he then had to protect her, because he knew that should always a be a target. Mr. Nobody then gave Han the heads-up when one of his best agents went rogue and when Deckard Shaw came for Han, Mr. Nobody had a way of staging Han's death, the scenes show's his death being "retconned" again of Deckard throwing Dom's cross necklace on the ground by Han's car and then scene shows his feet covering the shot of an injured Han and next is the shot of the car but without Han before it explodes, it's mentioned that Mr. Nobody had a way making things look real referring it to one of his "Magic tricks" and the next plan for Han was the hardest of them all, stay dead.