Show formatting marks if needed
Place the cursor before the page break
Press Backspace or Delete
In Microsoft Word, go to Home > Show/Hide to reveal breaks
Select the page break line
Press Delete
Use Find and Replace
Search for ^m
Leave Replace with blank
Click Replace All
For section breaks, select the break line
Press Delete
In Google Docs, click before the break
Press Backspace or Delete
Remove manual page breaks from the document layout settings if needed