Which authentication mode to connect to SSRS from .NET 5?

I wonder which authentication mode to use when accessing to an SSRS report server via .NET 5 app. I would like to use an HttpClient class, with the SendAsync method. I saw things like Basic authentication but the clients are relying on Blazor Web Assembly and I can’t see what domain to enter in the credentials. No, the ideal thing would be a simple pair username/password, without a domain.

Is it possible? and by using which authentication mode?

I would like to add that the app will be deployed on azure.

thank you.