Good for flat forms and quick additions
Use a text box for an answer line that is not clickable, a date beside a signature, a reference number or a note for the reader. If your PDF already has interactive fields, Fill PDF is usually faster and keeps answers aligned to those fields.
Match the page, within reason
Pick a supported font and a readable size that fits the space. The original document may use a custom embedded font that is not available for new text. Aim for a clean, readable addition instead of assuming a perfect match. Review special characters in the exported file.
Adding text is different from changing text
New text sits over the existing PDF content. It does not reflow a paragraph or remove the old wording. To revise a document’s original sentences, use its source file when possible. Covering words with whiteout is only a visual change, not secure removal.