Welcome to the Dell Community  @Tnjuguna 

Did you check the ZIF connectors???

Disconnect the AC adapter.

Remove the Main battery.

Peel back the black plastic flap in the center.

Carefully check/reseat the 4-6 ZIF connectors.

Dell Latitude E7450 Owner's Manual:

https://www.dell.com/support/manuals/us/en/04/latitude-e7450-ultrabook/late7450om/working-on-your-computer?guid=guid-9ccd6d90-c1d1-427f-9e77-d4f83f3ad2b6&lang=en-us

Best regards,

U2

Checked. Intact, still not working

Hi Tnjuguna,

You can try updating the BIOS and touchpad driver from the given link 

https://www.dell.com/support/home/us/en/19/product-support/product/latitude-e7450-ultrabook/drivers

If this doesnt fix kindly check the trackpad buttons and tap option is working in safe mode with networking?

Options to boot in Safe mode Windows 10 is provided in the link below.

https://www.dell.com/support/article/us/en/19/sln306359/how-to-boot-to-safe-mode-in-windows-10?lang=en