Deepthi, yes it is a common practice to keep these inputs and specs in an excel spreadsheet as part of the Design Requirements Matrix (DRM). This document may even be a live document that can only be seen by those on the design team and can be modified accordingly. In my recent experience, the DRM for a specific project has been posted on Sharepoint online for those on the team to comment on the inputs, specs, record meeting minutes, and make changes after the meetings.