You can't do anything without the password.
You can go to PDF unlock.com once you unlock it you own it once you own it you can converted and make adjustments as you see fit thanks for the reply
Depends on the encryption. Doesn't always work.
Plus, we do not discuss workarounds to Adobe security here on the Adobe site. If the person that supplied the pdf wanted them to change the document, they either would have removed the password or supplied it.