Perhaps reading/working/researching with the documentation would be of assistance:_Document.CheckGrammar Method
Begins a spelling and grammar check for the specified document or range.
Remarks
If the document or range contains errors, this method displays the Spelling and Grammar dialog box (Tools menu), with the Check grammar check box selected. When applied to a document, this method checks all available stories (such as headers, footers, and text boxes).
Reference:
_Document.CheckGrammar Method (Microsoft.Office.Interop.Word) | Microsoft Docs[^]Microsoft Support:
"Microsoft does not currently recommend, and does not support, Automation of Microsoft Office applications from any unattended, non-interactive client application or component (including ASP, ASP.NET, DCOM, and NT Services), because Office may exhibit unstable behavior and/or deadlock when Office is run in this environment."
https://support.microsoft.com/en-us/help/257757/considerations-for-server-side-automation-of-office[
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There really is no simple way to do this, as all of the functions that you would be calling generate modal windows that don't work to well when there is no one working on the server which is where the application is opening up.
Now there is OneDrive and/or Office365 which may allow you to embed an instance within a website; you may want to look at the complexity of that and see if it is worth it.