I would like to set as a template, sheets for project plans,
and to lock the frame / logo and other data, so that no one will be able to open without a password or confirmation from me.
Is there a way to do it?
And is it possible to convert the sheets / template file to dwg?
Everything else is possible except the password protection. If you need to distribute things in a protected or read-only format, PDF is the best option. You may need Adobe Acrobat to set passwords. Another possibility is to use an encryption application (even .ZIP achives can be password-protected but I understand that their protection is rather weak).
The intention is that it won’t be possible by others to edit the frame, frame data, logo, etc. of the project sheets,
but the inner surface. (others would be able to use/edit the inner surface of the sheet as they will, but wount be able to edit the frame/logo/other data)
I read a bit and realized that it is possible to lock layers- if that is possible; I wonder whether the locked layer can be unlocked by others, or there is a way to prevent it.