Microsoft SharePoint

Hey everyone, My users love Microsoft Excel , and so do I. I've been making tools for them in the form of workbooks for years, these tools usually have databases included in the spreadsheets or communicate to free APIs around the web, but now I want to distribute these tools in the form of Excel Add-ins for several reasons.

I want these Add-ins to communicate to a personal server to authorize users, read from my databases, and write to them while they're using their Excel environment. I have never built a website, so what would be a good solution for this, considering I'm new to all of these technologies? I know about the existence of Microsoft Azure , Microsoft SharePoint , and Google Sheets , but I don't know how to feel about those.

Currently, we are using WordPress in the organisation to deliver content externally to clients via a portal. However, we have installed way too many plugins for our liking, and they are starting to conflict with one another. Also, there were issues around scalability in the way we initially designed it. A few people in the organisation are leaning toward a Microsoft SharePoint solution using Livetiles, but we've been told it is mainly geared towards internal/intranet solutions as opposed to external solutions (which we provide). I was wondering if anyone has some high-level thoughts to share in regards to moving to a Microsoft Sharepoint environment vs. a more flexible solution like Umbraco .