1. The "group box that i have on my first tab" seems a seperated
ToolStrip control where some ToolStripTextBox ((used for address bar) and ToolStripButtons (used for Go, Back, Forward, Stop, Refresh,
If the "group box that i have on my first tab" is a part of your customized TabPage component, you'll need
to initialize the customized TabPage component (instead of standard TabPage component) as the 2nd TabPage.
2. Alternatively, you can check the following FAQ with code samples to make such Tabbed Web Browser.