This post contains links to topics that will introduce you to CODA if you are not familiar with the product, and also to this community and its structure.
It is a little different to the spreadsheet and word processors that we are used to. But it opens the door to a very powerful tool, that provides functionality far beyond spreadsheets and word processors can provide.
This post contains a Coda marketing video as an introduction. Less than 2 minutes.
In CODA - Getting Started - Part 1 there is a little more detailed explanation of basic Coda functionalities, using a Coda doc put together by Coda.
In CODA - Getting Started - Part 2 there is a link to a Doc called Learn that Coda prepared to provide a comprehensive learning experience of Coda functionality. I strongly recommend that you review this document, review the topics that interest you at the moment, but also regularly revisit it to gradually expand your general knowledge about the product.