By improving the connection between your foot and the pedal, you can ride longer with more comfort. Cycling shoes have stiff soles that transfer power more effectively to the pedals. If you would like to do some walking too, look for a shoe that is semi-flexible and has rubber knobs on the sole. Top models will have a sole that is fully stiff and an upper with several straps or buckles to tailor the fit
The pedals that came with your bike may be regular platform pedals. By upgrading to a pedal that engages directly to the shoe, you can use more muscle groups to power your way along. All the below are great combos and come complete with - Shoes, Pedals & Cleats.