Open the Word document
Go to File
Select Info
Click Protect Document
Choose Encrypt with Password
Enter a strong password
Confirm the password
Save the document
To restrict editing, go to Review
Select Restrict Editing
Choose the editing restrictions you want
Click Yes, Start Enforcing Protection
Set a password for protection
Save the document again
To mark as final, go to File
Select Info
Click Protect Document
Choose Mark as Final
Save the document
To remove access, store the file in a secure location
Share the password only with authorized users