HttpClient is what you're after.

To add headers, you simply create a custom HttpRequestMessage:

Dim client As New HttpClient()
Dim request As New HttpRequestMessage()
{
     RequestUri = New Uri("http://staging-exact-integration.posios.com/PosServer/rest/core/company"),
     Method = HttpMethod.Get,
}

request.Headers.Add("X-Auth-Token", "eyJhbGciOiJIUzI1NiJ9.eyJleHAiOjE0NTc3NTQ1")

Dim result = client.SendAsync(request).Result

HttpClient is what you're after.

To add headers, you simply create a custom HttpRequestMessage:

Dim client As New HttpClient()
Dim request As New HttpRequestMessage() With
{
     .RequestUri = New Uri("http://staging-exact-integration.posios.com/PosServer/rest/core/company"),
     .Method = HttpMethod.Get,
}

request.Headers.Add("X-Auth-Token", "eyJhbGciOiJIUzI1NiJ9.eyJleHAiOjE0NTc3NTQ1")

Dim result = client.SendAsync(request).Result