const options: AuthCodeMSALBrowserAuthenticationProviderOptions = {
    account: account, // the AccountInfo instance to acquire the token for.
    interactionType: InteractionType.PopUp , // msal-browser InteractionType
    scopes: ["user.read", "mail.send"] // example of the scopes to be passed
}
//^======HERE

// Pass the PublicClientApplication instance from step 2 to create AuthCodeMSALBrowserAuthenticationProvider instance
const authProvider: new AuthCodeMSALBrowserAuthenticationProvider(publicClientApplication, options), 
// =================================================== AND HERE====================================^

// Initialize the Graph client
const graphClient = Client.initWithMiddleware({
    authprovider
});