For general recreational riders, tire tread is an easy topic to understand.
Take a moment to think about where you plan to ride.
If you plan to stay on paved roads or paths, then a smoother tread will provide a smoother ride and will provide all the traction that you need. You can also use smoother tread off-pavement or if the pavement has some debris, but you will want to take some care to avoid losing traction.
If you think that you may ride off-road on dirt or gravel trails or paths, then a knobbier tread will give you the traction that you need on looser terrain.
Beyond the basic categories of smooth or knobby tires, tread variations have a negligible impact on your ride.
Once you have decided on a smoother or knobbier tire, it's mostly about what pattern is visually most appealing to you.
One last note... Bicycle tires, like car tires and motorcycle tires, often come with a directional tread. On cars, motorcycles, or on bicycles used at a high level of performance, the directional tread will help shed water and improve traction. For recreational riders, the tread can really go either way, but will look nicer if installed in the intended direction. If you are not sure which way the tread should go, there are several ways to tell. One, you can reference the other tire if already installed. Two, you can reference an arrow that is usually stamped into the sidewall and points in the intended direction of rotation. Or three, the directional tread will have a pattern that generally points toward the front.