Which VS That ( As relative pronouns !)
"Which" is used to give more information about something.
His best movie, which won several awards, was about the life of Gandhi.
"That" cannot be used instead of "which" in this meaning. ✓
"That" 👉 is used to introduce a clause without giving more information .
• There are lots of things that I need to buy before the trip.✓
• the people that live next door . ✓