How to find and access the Clock App for alarms on my iPad

It should be on one of your home screens. Its called Clock.

You can use the spotlight search or app library to find it.

click here ➜ Organize the Home Screen and App Library on your iPhone - Apple Support

The clock on the top left corner of the screen is a system service. It is not reliant on the existence of the Clock App on the device.

If you did completely delete it from the iPad, you can download it again from the App Store.

click here ➜ https://apps.apple.com/us/app/clock/id1584215688

The iPad User Guide is a rich source of information about your iPad and iPadOS. Here is a direct link to the relevant section of the Guide:

Set an alarm in Clock on iPad - Apple Support