Where are the connection ports on an iPad?

Depends on the iPad model - take a look at the Apple store:

https://www.apple.com/ipad/

There is ONLY one connection port.

An Apple Lightning port OR a USB-C port, ONLY currently found on the newest iPad Pro models.

The iPads that use the single Apple Lightning port still use a standard 3mm mini headphone jack.

That is it for connection ports!