The TabControl supports a Font property. You can change the font in the designer, and make it bold. You can do this programmatically as follows:
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tabControl1.Font = new Font(tabControl1.Font, tabControl1.Font.Style | FontStyle.Bold); |
The TabControl.Font controls the font for the tabs themselves. The TabPage.Font controls the font for the page contents (inherited but overridable by the contained contents).
If you are looking to have different fonts for different tabs within one tab control, this would have to be done through owner-draw work.