Protect a PDF with a password locally
Password protection can reduce casual access when a document must be shared, but it works only when the recipient can open the selected encryption format and receives the password safely.
Choose a unique, sufficiently long password and store it in a trusted password manager. The PDF and password are handled in the browser workflow; OpenToolSuite cannot recover a forgotten password.
Send the password through a different trusted channel from the document whenever possible. Putting the password in the same email as the attachment removes much of the practical protection.
Open the protected download in the reader your recipient is likely to use. Confirm that the password is requested and that every page opens correctly before deleting or moving any source file.
Encryption does not remove metadata, redact visible information, prove identity, or create a certified digital signature. Those are separate security and document-governance tasks.