Yes, Excel's security is not very secure, but they won't be able to paste the sheet back to the original file. Also if a user wants to remove the password a simple Google search will turn up macros that will remove it in seconds.
To answer your original question, some code can be found here that will prevent the user from copying and pasting :
We have a great community of people providing Excel help here, but the hosting costs are enormous. You can help keep this site running by allowing ads on MrExcel.com.
Allow Ads at MrExcel
Which adblocker are you using?
Disable AdBlock
Follow these easy steps to disable AdBlock
1)Click on the icon in the browser’s toolbar. 2)Click on the icon in the browser’s toolbar. 2)Click on the "Pause on this site" option.
Go back
Disable AdBlock Plus
Follow these easy steps to disable AdBlock Plus
1)Click on the icon in the browser’s toolbar. 2)Click on the toggle to disable it for "mrexcel.com".
Go back
Disable uBlock Origin
Follow these easy steps to disable uBlock Origin
1)Click on the icon in the browser’s toolbar. 2)Click on the "Power" button. 3)Click on the "Refresh" button.
Go back
Disable uBlock
Follow these easy steps to disable uBlock
1)Click on the icon in the browser’s toolbar. 2)Click on the "Power" button. 3)Click on the "Refresh" button.