How to set Build Action for binaries, added to Azure Function v2 project as "Copy to Output Directory"

I follow this sample: https://odetocode.com/blogs/scott/archive/2018/02/14/pdf-generation-in-azure-functions-v2.aspx

because I need to generate an image from HTML. I followed the instructions, downloaded the 32-bit binaries from DinkToPdf repository and added them to the project as seen below. Problem is I don't know how to do this part in particular:

I added the binary to my function app project and set the build action “Copy to Output Directory”. As we are about to see, the 32 bit address space is not a problem.

Why I don't have an option for "Copy to Output Directory" in my IDE?

And probably that's the reason I get the following exception:

Unable to load DLL 'libwkhtmltox' or one of its dependencies: The specified module could not be found. (Exception from HRESULT: 0x8007007E)

on this fragment:

arr = pdfConverter.Convert(new HtmlToPdfDocument() { Objects = { new ObjectSettings { HtmlContent = html } } });

Here is my full code:

using DinkToPdf;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Extensions.Http;
using Microsoft.Azure.WebJobs.Host;
using Microsoft.Extensions.Logging;
using System;
using System.Net.Http;
using System.Threading.Tasks;
using IPdfConverter = DinkToPdf.Contracts.IConverter;

namespace Html2Img
{
public static class HtmlToImage
{
    [FunctionName("HtmlToImage")]
    public static async Task<IActionResult> Run([HttpTrigger(AuthorizationLevel.Anonymous, "get")]HttpRequest request, ILogger log)
    {
        log.LogInformation($"Converting {request.Query["url"]} to Image");

        var html = await FetchHtml(request.Query["url"]);
        var pdfBytes = BuildPdf(html);
        var response = BuildResponse(pdfBytes);

        return response;
    }

    private static FileContentResult BuildResponse(byte[] pdfBytes)
    {
        return new FileContentResult(pdfBytes, "application/jpg");
    }

    private static byte[] BuildPdf(string html)
    {
        byte[] arr = null;

        try
        {
            arr = pdfConverter.Convert(new HtmlToPdfDocument() { Objects = { new ObjectSettings { HtmlContent = html } } });
        }
        catch (Exception ex)
        {
            System.Diagnostics.Debug.WriteLine(ex);
        }

        return arr;
    }

    private static async Task<string> FetchHtml(string url)
    {
        var response = await httpClient.GetAsync(url);
        if (!response.IsSuccessStatusCode)
        {
            throw new InvalidOperationException($"FetchHtml failed {response.StatusCode} : {response.ReasonPhrase}");
        }

        string str = string.Empty;

        try
        {
            string s = response.Headers.TransferEncoding.ToString();
            str = await response.Content.ReadAsStringAsync();
        }
        catch (Exception ex)
        {
            System.Diagnostics.Debug.WriteLine(ex);
        }

        return str;
    }

    static HttpClient httpClient = new HttpClient();
    static IPdfConverter pdfConverter = new SynchronizedConverter(new PdfTools());
}