Resident Evil Requiem: Grace's origins make no sense and I need answers

!Am I the only one confused about what the fuck Grace actually is?? Like is she a clone or not? She looks exactly like kids from experiments done 14 years before she was born, she's immune to the T-Virus and nobody explains why. Did any of you actually understand her backstory or are we all just pretending it makes sense lol!<

!I need a lore expert to set me straight because I'm lost. Sorry in advance if I missed something obvious, I've beaten the game 4 times and I'm still confused.!