using (var ctx = new ClientContext($"{SpRoot}/{SpPathToFolder}"))
{
    ctx.Credentials = new NetworkCredential("username", "password", "domain");
    using (ms)
    {
        Microsoft.SharePoint.Client.File.SaveBinaryDirect(ctx, targetFileUrl, ms, true);
        ctx.ExecuteQuery();
    }

Web site = ctx.Web;
ctx.Load(site);
ctx.ExecuteQuery();

var client = new HttpClient(handler);
        client.DefaultRequestHeaders.Accept.Clear();
        client.DefaultRequestHeaders.Add("Accept", "application/xml;odata=nometadata");

        HttpResponseMessage response = client.PostAsync(restUrl, null).Result;