Why is this byte throwing a null exception in my Program.cs

Question

Code in my Program.cs Dont judge me but i am trying to make a imgui(replica) for a roblox exploit because someone requested it I dont know waht do add here it is just saying i need to add details so what i am trying to do with this is pack the dlls that i referenced

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace ImguiBase
{
    static class Program
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            AppDomain.CurrentDomain.AssemblyResolve += (Object sender, ResolveEventArgs args) =>
            {
                String thisExe = System.Reflection.Assembly.GetExecutingAssembly().GetName().Name;
                System.Reflection.AssemblyName embeddedAssembly = new System.Reflection.AssemblyName(args.Name);
                String resourceName = thisExe + "." + embeddedAssembly.Name + ".dll";

                using (var stream = System.Reflection.Assembly.GetExecutingAssembly().GetManifestResourceStream(resourceName))
                {
                    Byte[] assemblyData = new Byte[stream.Length];
                    stream.Read(assemblyData, 0, assemblyData.Length);
                    return System.Reflection.Assembly.Load(assemblyData);
                }
            };
            Application.Run(new Form1());
        }
    }
}

The Exception i am getting is this https://gyazo.com/660dfbc4661f11c1b05c7ff287d710b5