Hi Prabath, I am John J.D., a fellow Microsoft user like you.
Use the Keyboard Shortcut > Try pressing the keyboard shortcut to enable or disable your touchpad. Many laptops have a function key (often labeled as "Fn") combined with another key that has a touchpad icon. It's different for various laptop brands, so look for the touchpad icon on your keyboard.
If issue persists, here are some steps you can try to re-enable your Synaptics pointing device driver without using a mouse or touchpad:
> Press the Windows + X key to open the Quick Link menu.
> Use the arrow keys to navigate and select "Device Manager," then press Enter.
> Inside Device Manager use the Tab key to navigate within Device Manager and use the arrow keys to locate and expand the "Human Interface Devices" category.
> Navigate to the Synaptics device driver using the arrow keys and press Enter.
> You should now be in the properties window of the device. Use the arrow keys to go to the "Driver" tab and press Enter.
> Inside the "Driver" tab, select "Enable Device" using the arrow keys and press Enter.
If these steps do not resolve your issue, you may need to consult with a professional or contact Lenovo’s customer support for further assistance.
John J.D.