One of my friend said she wants to write a story for fun since it's the school holidays at...

One of my friend said she wants to write a story for fun since it's the school holidays at the moment and asked me if it's good:
It's about a group of friends and mc as well as another group of friends being swallowed by a portal or something idkk both group are kind of strangers but they go to the same school I think
then they have to survive together, in a magical world
It's horror, supernatural, and maybe the subgenre she said a slow burn but she's not sure
She said it's just the basis like how she plan to start it all (i need to ask her again)
Honesty idk what to tell her whether it's good or not
HELPP