Well, probably adjustment and self - confidence. In the story, the characters might be adjusting to a new environment, which is a common theme. Also, self - confidence could play a role. If someone has first day jitters, they need to build up their self - confidence to overcome those feelings.
The main themes could be about new beginnings, nervousness, and facing the unknown. New beginnings because it's the first day, which often represents a start of something new like a new school year or a new job. Nervousness as the word 'jitters' implies being uneasy or worried. And facing the unknown since starting something new usually comes with uncertainties.
Chapter 738, "Here to Fight!", is the clearest early answer because the buildup finally cashes out in a real clash. A useful checkpoint is the way the scene starts with Feeling that something was amiss, he immediately called Jiang Li.
Chapter 743, "They Have Already Been Released", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event. A useful checkpoint is the way the scene starts with Too many people caused a commotion at Fang Family's place tonight,...
Chapter 531, "She Really is a Remarkable Person", is the clearest early answer because it turns Pei Ye's situation into a concrete plot event.
Chapter 779, "Unmarried but Have a Daughter?!", is the clearest early answer because it turns Chen Qijun's situation into a concrete plot event. The chapter turns that into something concrete by moving from Right, there's one more important thing," Shen Lan looked at Chen...
Chapter 685, "Defense Value Skyrockets!", is the clearest early answer because it turns Wu's situation into a concrete plot event.
Chapter 851, "Peace Charm", is the clearest early answer because it turns Shi Lei's situation into a concrete plot event. It opens with She initially came with the expectation of becoming the Gu Family's... and closes on The Old Madam also looked at Jiang Li..
The best chapter pointer here is Chapter 15, "The Autistic Teen Jiang Shixu". It opens with Jiang Shixu woke up from those nightmares filled with blood and darkness,... and closes on Since she didn't move, Jiang Shixu also stayed put, and the kitchen, which....
Chapter 922, "The Good Deed You Did!", is the clearest early answer because it turns Rong Kexi's situation into a concrete plot event.
Chapter 570, "A Simple Auto-Attack Baits Out an Ultimate from the Enemy", is the clearest early answer because the buildup finally cashes out in a real clash. It opens with What the heck is that?" "?? and closes on It was impossible for Jiang Li not to know; her family had been....
A practical answer is Chapter 8, because it turns the idea into a concrete scene. The chapter opens with The resentment that had barely calmed among the crowd surged back two..., adds pressure through Why keep harping on the fact that he wasn't a decent man?, and ends on Other people with a.