Delete the pages you do not want — a blank scan, a duplicate, an annex that should not leave the office — and keep the rest as a clean document.
Removing a page is permanent in the file you produce: the page is not there anymore, and nobody can scroll to it. If your goal is to hide a paragraph or a photo inside a page that must stay, this is not the tool — use Redact instead, which strips the underlying content rather than drawing a black box over it.
The page field takes a list and ranges: 1, 3-5, 1,4,7-9. Pages are counted from 1 as they appear in the file, so check the count first — a scan that includes a blank first page shifts everything by one.
Removal is irreversible in the output. Keep your own copy of the original until you are sure the result is what you want to send; the site does not keep it for you.
Not from this site: the output is a new file. Re-run the tool on the original document if you removed too much.
Yes. Pages are copied as-is, so a scan stays a scan.
Yes, with a range such as 1-3,7,12-15.