You'll need a PPL (Private Pilots License) before you can get a CPL (Commercial Pilots License). After that you'll need VFR (Visual Flight Rules) and/or IFR (Instrument Flight Rules) ratings for whatever plane you are going to fly.
There's a wiki page thats actually quite in depth in explaining Pilot Certification in the US.
In the US: at least a commercial pilot certificate with multiengine and instrument ratings. Some flight experience--somewhere between 500 and 1500 hours is looked for to get hired.