Deleting text from a repeating Word header can remove it from more pages than intended. To leave a cover page without the usual header, use the separate first-page header rather than erase the ordinary one.
Check two pages in a copy
In desktop Word, open a copy and double-click the header. Select Different First Page. Inspect page one and page two: the first-page area is separate, while the ordinary header should remain on later pages. Add or remove content only in the area you mean to change. The same distinction can apply to footers.
For example, keep a report title on page two onward while leaving the cover blank. Do not insert a stack of empty paragraphs to push the header away.
Watch section boundaries
If the document contains several sections, inspect their headers and Link to Previous settings before changing them. Headers and footers link separately. Different First Page is not a general command for removing any arbitrary page’s header.
Save, reopen and inspect the cover, page two and each section start. Check the exported PDF too: the final reader sees that layout, not the editing controls.