can you describe the difference between Blazor vs Razor.
Blazor is an SPA framework (runs in the browser) within the ASP.NET Core family of web frameworks. Razor is a markup language for rendering HTML. Razor Pages is a server side web framework in ASP.NET Core if that's what you mean by Razor.
Which one is better for long term enterprise level application?
Your question makes incorrect assumptions. The official documentation covers the basics.
How long Blazor will support?
No one can accurately answer this question.
what the future of Blazor for enterprise level projects?
This question is far to vague to answer. Again, Blazor is an SPA that runs in the browser. An enterprise application is made of many more parts than an SPA application. However, ASP.NET Core has everything needed to build an enterprise application.
Please mentions anything with good reference.
Your questions is feels like you recently started researching. I recommended going through the ASP.NET Core fundamentals which illustrates the different tools the framework has to offer.