There are two simple ways to remove the password from a PDF file, one of which works no matter what software you have.
You can password protect a folder in Windows 10 using a program called WinRar, which is free to download and use.
To remove the password from a PDF on Windows, open the PDF, press Ctrl+P, then select "Save as PDF" as your printer. On macOS, open the PDF in Preview, press Command+P to open the print dialogue, then ...