Form1.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void toolStripTextBox1_KeyDown(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter)
            {
                string url = toolStripTextBox1.Text.Trim();
                webBrowser1.Url = new Uri(url);
            }
        }

        private void toolStripButton5_Click(object sender, EventArgs e)
        {
            string url = toolStripTextBox1.Text.Trim();
            webBrowser1.Url = new Uri(url);
        }

        private void toolStripButton2_Click(object sender, EventArgs e)
        {
            webBrowser1.GoBack();
        }

        private void toolStripButton3_Click(object sender, EventArgs e)
        {
            webBrowser1.GoForward();
        }

        private void toolStripButton6_Click(object sender, EventArgs e)
        {
            webBrowser1.Refresh();
        }

        private void toolStripButton4_Click(object sender, EventArgs e)
        {
            webBrowser1.Stop();
        }

        private void toolStripButton1_Click(object sender, EventArgs e)
        {
            webBrowser1.GoHome();
        }

        private void webBrowser1_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
        {
            tabPage1.Text = webBrowser1.Document.Title;
            
        }
    }
}