How to detect touch inputs; how to add a new button on UI that triggers events on game?

If I add a new canvas, there are warnings about duplicate event handlers. If I delete the event handler no GUI buttons are interactive.
What is the recommended way to add a new button to the UI?
Regarding the input I found the only way to detect touch is via tap handler.
This way if I tap an object the player goes to that object and when he arrives at the destination the code is executed.

If there another way? I am looking to make a joystick to control the character, is this possible?

UI support is coming in our 0.6 release and more in our 0.7 release. Highrise uses ui toolkit so input via UGUI is not currently supported. The 0.6 release should be out very soon.