The Minor Illusion cantrip lets you create an auditory, visual, olfactory and gustatory (taste and smell) illusion. For instance, you can make a sound seem to come from somewhere other than the direction it’s coming from or make someone taste something they’re not actually tasting.
The spell requires concentration and is sustained by your channeled energy like any spell. It won’t last for more than one 5 Minute period at a time unless you get Idle Hands to extend its duration past 3 hours. If the spell is broken during that time, either due to touching or Dispel Magic spells or hostile actions against it/you break concentration forcefully enough, the illusion instantly dissipates without harming anyone in the area of effect.