How to protect and hide cells from view for employees in google spreadsheet?

Question

Google Sheets

There is a work schedule in a Google spreadsheet, it is necessary to provide access to personal access employees without publishing a page on the Internet for general use.
There are also sheets for each month in the file - and I would also like to limit the display - for example, so that users see only specific sheets, for example, the current and next month.
And the third subtask is to hide some data that is in separate cells for display.
At the same time, it is necessary to protect the document itself from copying and downloading.
--
Tell me how to implement it?
It may be necessary to use two tables - one source - and the other automatically copies everything that is on the source, but only those cells that are specified.
Only wat I can’t find how to copy only what is needed and not the entire document into a new blank table and that it would update all the changes itself.
Perhaps there are other solutions.

Answer 1

the third - nothing
the second - pick, there are settings for hiding sheets by the document's owner, and the impossibility of opening by viewers is the
easiest - as they themselves decided, for everyone - one, controlled from the other

Answer 2

And the third subtask is to hide some data that is in separate cells for display

Setting the format ;;; can be hidden visually from the sheet, but will be visible in the formula bar.

Answer 3

and how to copy (synchronize) from one table - information from another?

Answer 4

I came across this solution to this problem:
https://yandex.ru/q/question/science/kak_skryt_ot_...