How do I delete a network on my iPad?

To do this you will need to be in range of the network and have wifi turned on. In the list of available networks, tap the blue arrow at the right and select "forget this network" to remove it from the iPad's list of known networks.

It will still show up in the list but will not automatically connect when detected.

Not sure what you mean. Are you connected to one specific router and wish to change to another? Go into settings and choose another. Or, turn off wifi if you want to disconnect. or use airplane mode.