iBook

Hello Sumneja,

Thanks for choosing the Apple Support Communities. We understand you're looking to change font sizes using Apple Books on your iPad. We have a user guide specifically set up for iPadOS 16 that will help you get this done. Check out the steps below.

Read books in the Books app on iPad - Apple Support

"Change the text and page appearance

1. Tap the page, tap  at the bottom of the page, tap Themes & Settings, then do any of the following:

• Change the font size: Tap the large A to increase the font size or tap the small A to decrease it.
• Change the font: Tap Options, tap Font, select a font option such as Georgia or Palatino, then tap Done.
• Turn on vertical scrolling: Tap  to scroll continuously through a book.
  • For PDFs, tap , at the top of the screen then turn on Vertical Scrolling.
  • Adjust the display brightness: Tap , then choose an option.
  • Change the page background color: Tap a page theme such as Quiet or Bold.
  • Make the font bold: Tap Options, then turn on Bold Text (green is on).
  • Customize spacing and justification: Tap Options, turn on Customize (green is on), then drag the sliders left or right to adjust line spacing, character spacing, and word spacing. You can also turn Full Justification and Allow Multiple Columns off or on (green is on).

Tap Done to apply your changes."

We hope this helps.

Cheers!