I need some help with my short story, just some suggestions, thanks?

This is just a description of a scene that I was to write for my english class, based off of a conversation that you overheard. So far, I have only some the description and the setting..My assignment is only supposed to be concrete, nothing abstract. I need to still add structure and description to the dialogue. I realize that I posted this same story a little while ago, but I'm asking a different question this time.

1) Should I name the characters? Or just describe them better a bit? Because I feel like the words "guy" "boy" "girl" "he" and "she" are starting to look really redundant after a while.

2) I'm rally stuck onto how to merge the dialogue into the story. Should I leave it as a script just the way it is and add random details in brackets? or make it like an actual story, where I can describe in a concrete fashion what the character are doing to show their emotion? I just dont know what to do with it because its such a dumb overheard conversation and I HAVE to use this one because that's what my TA told me was mandatory.

Thanks so much for everyone that has already and is going to help me, I really appreciate it.

Here is the description:

Blue walls, a deep turquoise blue. On the walls hang little paintings, with inspiring quotes on them. A single bed against the window, a green shag rug. On it sit a guy and a girl, huddled around a laptop with coffee cups in their hand, leaning against the bed. A mirror hangs, on the adjacent side of the room, framed with faded pictures and old memories. In the mirror, a reflection can be seen, of the study table, cluttered with books, medals and trophies as if to hide the girl’s various accomplishments. The boy reaches over to the dark oak side table beside him, slowly sliding his fingers across the smooth surface, stopping now and then, to touch the various trinkets that sit atop it. The girl watches as his mouth contorts into a soft smile before he turns his bright blue eyes around to face her. She lifts up a slender finger to flick the long, black locks of hair out of her face. The charm bracelet on her arm jingles. Below sparse lace of cardigan, goosebumps. The boy shuffles over and reaches back for his grey sweater and swiftly puts it around the girl’s shoulder. She smiles gratefully.

The girl reaches over with her blood red painted nails and hits the green triangle on the screen. Then she pulls the hoodie more securely around her shoulder. The screen goes blank and her shoulder tenses. They stare intently at the buzzing screen; heads so close they were almost touching, the coffee cups all but forgotten. Slowly, as the music begins, she relaxes back against the bed. A movie starts playing on the screen. The guy glances over at her. Their eyes meet, he grins at her. Slowly the guy brings the cup of scalding hot coffee to his lips as he carefully watches colour rise up to the girl’s cheeks. She blushes and looks away.

The movie ends, music stops, the screens goes blank again. The room is enveloped in a peaceful silence as the girl and her companion sit on the green shag rug, thinking. The bright blue light of the alarm clock on the side table changes as the minutes pass. 5 minutes pass. As the clock hit 7:07, suddenly, as if raised from a slumber, they look up at each other, almost simultaneously. The wheels turn, in their head, as the same idea comes to both of them. Slowly, the girl reaches over to her side table and picks up a crinkled up piece of paper with the project details on it. She holds up the paper and carefully starts reading; the boy follows her bright hazel eyes as they scan the piece of paper. A dent appears in the middle of her forehead as she furrows her stick thin eyebrows in concentration. She sighs, and looks up briefly to notice her companion looking at her. Letting her dark black tresses fall from her shoulder so they covered her face, she continues to scan the piece of paper. She looks up slowly as a grin spreads across her beautiful face, putting her pearly white teeth on full display.