Using API HTTP Request

I was able to get it to work by doing Invoke code like the last post said.

string boundary = DateTime.Now.Ticks.ToString("x");
string LoanDocumentIdentifier = api_Object.SelectToken("LoanDocumentIdentifier")?.ToString() ?? "";
string url = api_Object.SelectToken("url")?.ToString() ?? "";
string fieldKey = api_Object.SelectToken("fields.key")?.ToString() ?? "";
string fieldXamzAlgorithm = api_Object.SelectToken("fields.x-amz-algorithm")?.ToString() ?? "";
string fieldXamzCredential = api_Object.SelectToken("fields.x-amz-credential")?.ToString() ?? "";
string fieldXamzDate = api_Object.SelectToken("fields.x-amz-date")?.ToString() ?? "";
string fieldXamzSecurityToken = api_Object.SelectToken("fields.x-amz-security-token")?.ToString() ?? "";
string fieldPolicy = api_Object.SelectToken("fields.policy")?.ToString() ?? "";
string fieldXamzSignature = api_Object.SelectToken("fields.x-amz-signature")?.ToString() ?? "";

  try	
  {	 
	using (var client = new System.Net.Http.HttpClient())
	{
		var request = new HttpRequestMessage(HttpMethod.Post, new Uri(url));
		var content = new MultipartFormDataContent(boundary);

		content.Add(new StringContent(fieldKey), "key");
		content.Add(new StringContent(fieldXamzAlgorithm), "x-amz-algorithm");
		content.Add(new StringContent(fieldXamzCredential), "x-amz-credential");
		content.Add(new StringContent(fieldXamzDate), "x-amz-date");
		content.Add(new StringContent(fieldXamzSecurityToken), "x-amz-security-token");
		content.Add(new StringContent(fieldPolicy), "policy");
		content.Add(new StringContent(fieldXamzSignature), "x-amz-signature");
		content.Add(new ByteArrayContent(in_pdf_byte_array), "file");

		request.Content = content;

		HttpResponseMessage response = client.PostAsync(url, content).Result;
		response.EnsureSuccessStatusCode();
		out_status_code = response.Content.ReadAsStringAsync().Result;
	}
  }
  catch(HttpRequestException e)
  {
	  out_status_code = e.Message;
  }

I just wasn’t able to get it working with UiPath API HTTP Request. This is something you’re able to help me with?