Add headers and footers to document sections, including different headers for the first page.

1. Adding a Default Header 

section = doc.current_section
header = Uniword::Header.new(type: 'default')

para = Uniword::Paragraph.new
para.add_text("Page Header", bold: true)
para.align('center')
header.add_element(para)

section.default_header = header

2. Adding a Footer with Page Numbers 

footer = Uniword::Footer.new(type: 'default')

para = Uniword::Paragraph.new
para.add_text("Page ")
# Add page number field
para.add_text("1", field_type: 'page_number')
para.align('center')
footer.add_element(para)

section.default_footer = footer

3. Different Headers for First Page

Use separate header types to differentiate the first page:

# First page header
first_header = Uniword::Header.new(type: 'first')
para = Uniword::Paragraph.new
para.add_text("First Page Header")
first_header.add_element(para)
section.first_header = first_header

# Default header for other pages
default_header = Uniword::Header.new(type: 'default')
para = Uniword::Paragraph.new
para.add_text("Default Header")
default_header.add_element(para)
section.default_header = default_header

To use odd/even page headers, set section.different_first_page = true and assign both odd_header and even_header on the section.