You can use Tools | Protection with either or both
Protect Sheet
Protect Workbook
options (one at a time) with a password.

But these 'protection' methods are not for true security or to protect your
formulas and such from being discovered. They are mainly there to keep
accidental changes from being made to the format/content of the worksheets or
workbook as a whole.

But quite frankly this is very weak protection. Passwords for both
worksheets and workbooks are easly discovered. And even if a person does not
figure out the password, a truly determined individual can duplicate the
workbook through other means.

"Kelvin" wrote:

How can I protect my worksheet to copy and paste to another new worksheet?