What the subject wants to ask is how to unlock the second floor of Dad's noodle restaurant. Dad's noodle restaurant is the way to unlock the second floor:

1. Players need to unlock two rooms on the first floor, namely noodle restaurant and vinegar room.

2. Unlocking the noodle restaurant needs to complete all the menu tasks on the first floor, and unlocking the vinegar room needs to complete all the hot and sour potato shreds on the first floor.

3. After the player completes these two tasks, the second layer will be automatically unlocked.