The academic hall has compiled the model of the first-level title and the second-level title of English papers for your reference:

First-level title chapter 1? (Small two, bold, centered, number Times New Roman, one character in the middle, before and after the paragraph 18 point)

Secondary title 1. 1? (small three, bold, left-aligned, number Times New Roman, one character in the middle, before and after the paragraph 13 point)