Just to clear up some terminology, when you say ‘on touch’ are you referring to an IOS touch screen event, or do you mean “When this object is touched by the player object” or something similar?
Both would be handled similarly, only difference would be the event you use. In the actor’s blueprint you can right click on any of your components and add an event, such as “OnInputTouchBegin” and then you can wire the execution not from that to a node such as “set actor rotation” or similar.
So the process would be, in your static mesh blueprint, add a collision component (or use collision on your static mesh) and then right click that component in the list in the left pane and add an event of the type you want, then wire that up to whatever you want to have happen when the event triggers.