So I thought I'll post some info on here for the ones that can't be arsed to ask for it !
Gambit (Remy LeBeau):
Gambit grew up in the cajun culture of Louisiana, raised by The LeBeau thieves guild clan he grew up to be a master-thief.
He was involved in the slaughter of a group of mutants, before he met the x-men, called the Morlocks. This history has plagued him with guilt and is a reason why he remains such a wild card in terms of which side of the law he walks on.
When he joined the x-men after meeting a young Storm he wasn't trusted within their ranks as they didn't know a great deal about him.
Gambit has had an on/off relationship with Rogue (Anna Marie) which has helped him settle down into a more stable and trustworthy role within the team. Gambit considers himself to be a ladies man and often gets the girl he wants so the lack of sexual contact between himself and Rogue because of her dangerous power puts a lot of strain on their relationship.
Gambit has left the x-men various times and joined other teams or just gone off on his own. Being a loner that flits from job to job, bed to bed, kill to kill is what Gambit used to be and a part of that remains.
His power is the ability to charge up kinetic (moving) energy and channel the energy into objects. His most famous move would be charging a deck of cards with energy and throwing them to explode on impact. He also uses a staff for combat.
This one's a toughie to summarize because she's such a complicated character.
Jean was in the original class of x-men as a telepathic mutant. She was a loving and caring person that looked after everyone in the x-men and genuinely cared about the human race. Her powers grew to "omega level" yet she still dealt with it very rarely unleashing her full power.
Jean has lived with the x-men since she was a very young girl and eventually built a family there. She fell in love with Scott Summers (Cyclops) and married him, she had Charles Xavier who was like a father to her, a daughter from an alternate reality called Rachel Summers. Wolverine and her became extremely strong friends and often became closer than that when Logan fell in love with her.
Unfortunately Jean was possessed by an extremely powerful alien life-form called the "Pheonix Force" which gave her more power yet ultimately began to take over her and become a threat. Jean killed herself to stop the Pheonix killing everything. But as the name suggests the Pheonix and Jean Grey rose again rejoining the x-men. She fought to have a normal life with Scott and her friends (as normal as things get being part of a mutant super team) but has since been killed yet again and not yet been resurrected.
When writing a story based on an existing franchise like the X-men we need to stay true to the characters and world they live in so hopefully these bios will help you to understand them more.
Feel free to message me any questions you have about the x-men and such :)