The Start menu opens when you click the Start button on the taskbar. If the taskbar is not visible, it may be hidden or greatly reduced. To find it and make it always visible, follow these steps.
Instructions
Step 1
If the taskbar is reduced to a very small size, move the mouse cursor over the area of its location. When the pointer turns into a vertical double-headed arrow, press the left mouse button and drag the border up.
Step 2
If auto-hide is enabled, move the mouse cursor to the very bottom of the screen, then to the top and sides. The panel should appear.
Step 3
Right-click on it and select Properties.
Step 4
On the "Taskbar" tab, check the boxes in the following lines: "Dock the taskbar" and "Show the taskbar on top of other windows". Uncheck the "Automatically hide taskbar" checkbox.
Step 5
Click the "OK" button to save the changes.