Sharing Excel File for multiple user Input

Hi all, hope this is the correct forum (general) as unsure what function this request will actually require.

Basically wanting to share a workbook with colleagues and have some data only added by owner, other data added by shred users.
Some data to be editable by both owner and user.
I have added more details to the sheet. Hope its clear enough.
This will be just the starting point for this workbook. Most other additions I can add myself.
I have never managed to share a book successfully yet so thought I would try the experts.
Thought I would get this part working before progressing otherwise would be little point.

thanks in advance to all that take the time to take a look.

Maax.