.NET Core WebApi + Angular Authentication & Authorization via applications in Microsoft Azure

Thankyou Manish. Posting your suggestion as an answer to help the other community members.

from the provided architecture in BE code add the list of valid audiences as per the below image make it to true

Below is the sample code where you can check the valid audience code.

services.AddAuthentication(cfg =>
{
    cfg.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
    cfg.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
})
.AddJwtBearer(opt =>
{
    opt.Authority = "https://login.microsoftonline.com/common";
    opt.Audience = "api://A134d6c8-8078-2924-9e90-98cef862eb9a"; // Set this to the App ID URL for the web API, which you created when you registered the web API with Azure AD.

    opt.TokenValidationParameters = new TokenValidationParameters
    {
        ValidateIssuer = true, 
        ValidateAudience = true, 
        ValidAudiences = new List<String>
        {
            // you could add a list of valid audiences
            "A134d6c8-8078-2924-9e90-98cef862eb9a"
        }, 
        ValidIssuers = new List<string>
        {
            // Add tenant id after https://sts.windows.net/
            "https://sts.windows.net/{YourTenantId}"
        }
    };
    opt.Events = new JwtBearerEvents()
    {
        OnAuthenticationFailed = AuthenticationFailed
    };
});

For complete information check the SO.