I have an Employee Salary sheet, which I don't want to share with someone.

To protect this, we have to go to the Review tab first.

And there you will find 2 options

1- Protect Sheet

2- Protect Workbook

Here I want to protect only this Employee Salary sheet

Click on it, and a popup will appear

Now this sheet is protected and you can’t change the data

We can unprotect the sheet with the password

By clicking "Protect Workbook" we can lock the whole workbook, also we can't create a new sheet there.