1
Open the Settings App.
Go to Personalization - Taskbar.
Check if the option to hide the Taskbar is enabled, if so, disable that setting.
2
If that does not resolve the problem, open Task Manage.
Select the Processes tab.
Find the Windows Explorer task, right click it and select Restart, the screen will go blank for a second or two, then check if the Taskbar is back.
3
If that does not resolve the problem.
Open the Settings App (Windows Key + i).
Go to System - Recovery.
Click the 'Reinstall Now' button in the 'Fix problems with Windows Updates' section and wait for that process to complete, this process does not affect your files, settings or installed apps.