If you say SQL Server Data Tools SSDT is a set of tools to work on database projects from Visual Studio for example. But it is for development, deploy. Not to work in applications.
If you want support in your ASP.NET web app for reading Excel spreadsheets then you should use the
components
That they are libraries that will help us to manipulate our office documents. For example, extract or edit the calculation sheets. For example to parse excel ...
And after you have the data parsed in an array or business object of your app, then it only remains to take them to DB through your data or services layer. But this is another issue. Here is the only thing I recommend if it is a large volume of data the best option is to Batch SQL
Links that can help you
I hope it can help or guide you