Call soap from aws lambda in C#

I’m new on serverless lambda functions and I have deployed a simple soap api by using C# and I want to know how to call it from a lambda function.
In VS you add the reference but what about lambda? I can’t figure out the option

I’ve tried to add the reference with no luck

There isn't a pre-scaffolded method to interact with a SOAP service using a Lambda function.
You'd need to handle it "manually" by creating the XML input, sending it through an HTTP request, and then parsing the response.

Here's a sample using Python, but you can achieve this in any programming language that Lambda supports:

import json
import requests
from datetime import datetime, timedelta
from xml.dom import minidom

import os

url = os.environ['SERVICE_URL']

query_service_template = """
    <?xml version="1.0" encoding="utf-8"?>
    <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
    \t<soap:Body>
    \t\t<SimpleQuery xmlns="http://example.ws.localhost/">
    \t\t\t<m_field>%s</m_field>
    \t\t</SimpleQuery>
    \t</soap:Body>
    </soap:Envelope>
    """

def build_body(field):
  body = query_service_template % (field)
  body = body.replace("\n", "")
  return body.encode('utf-8')

def build_headers(request):
  return {
    "Content-Type": "text/xml; charset=utf-8",
    "Content-Length": str(len(request))
  }    

def extract_data_from_xml(response_body):
  xmldoc = minidom.parseString(response_body)
  outputField = xmldoc.getElementsByTagName('outputField').item(0).firstChild
  
  return {
    'outputField': outputField,
  }
  
def lambda_handler(event, context):
  # Build request
  request = build_body(event['input_field'])
  
  # Build session
  session = requests.session()
  session.headers = build_headers(request)
  
  # Post request
  response = session.post(url=url, data=request, verify=True)
  
  # Extract data from response
  
  data = extract_data_from_xml(str(response.content, "UTF-8"))
  
  return data