The Start Menu on Windows helps you quickly search for applications, view recently used files,... But if the Start Menu disappears, it will affect your work and basic operations on the computer. Below are some ways to restore the disappeared Start Menu on Windows computers.
Restart Windows Explorer
Restarting Windows Explorer is often effective in fixing system-related issues, such as the Taskbar or Start Menu.
Press Ctrl + Shift + Esc to open Task Manager, then click on the Processes tab and find Windows Explorer .

Now click the Restart task button in the upper corner to restart the Start Menu.

Turn off auto-hide Taskbar
If you accidentally enable the setting to automatically hide the Taskbar when not in use, the Start Menu may disappear as well. So check the settings again and show the Taskbar again.
Open Settings on your computer, then click on the Personalization tab in the left menu and click on Taskbar to adjust.

Switch to the interface as shown, the user will expand the Taskbar behaviors settings .

Finally turn off the Automatically hide the taskbar setting .

Re-register Start Menu packages
Re-registering the Start Menu installation packages will restore the original Start Menu and will not affect the system.
Press Windows + S key combination to open the search menu, then type powershell and select Run as administrator .

Now enter the command below and press Enter to run the command.
Get-appxpackage -all *shellexperience* -packagetype bundle |% {add-appxpackage -register -disabledevelopmentmode ($_.installlocation + “\appxmetadata\appxbundlemanifest.xml”)}

Scan for corrupted files
Windows has a useful tool called System File Checker (SFC) that can scan your PC for corrupted system files and repair them.
Press Win + X key combination and then click Terminal (Admin) from the list.

The new interface appears, the user types sfc /scannow in the interface and presses Enter.

Wait for the scan to complete, then restart your computer.
Using System Restore
Sometimes a faulty Windows update, a virus-infected application, or an unwanted system change can cause the Start menu to suddenly disappear. You can use the System Restore tool to fix the problem.