When comparing the two licences in aviation the Private Pilot License (PPL) (PPL) and the Commercial Pilot License (CPL) (CPL) one of the most important distinctions is the number of flying hours required. According to the article on PILOT CET's blog for a PPL you typically need a minimum of about 40-60 flying hours. On the other hand, for a CPL you need a minimum of around 200 flying hours. So in short: to move from hobby oriented flying to professional commercial flying the required flying time jumps significantlyfrom tens of hours (PPL) to a couple of hundred hours (CPL).
Under the broader topic How Is a CPL Different from a PPL the difference in flying hours reflects the difference in the level of training responsibility and usage:
With a PPL the licence is mostly for personal recreational or hobby flying. You're not flying for hire or reward. The flying hours required are modest because you are building basic competency.
With a CPL you're being trained and certified for commercial operations carrying passengers possibly flying complex aircraft meeting stricter regulatory standards. Thus the infrastructure skills and flight hours are much higher.
If you're asking How many flying hours do I need for a CPL versus a PPL plan for roughly 40-60 hours for a PPL and at least 200 hours for a CPL (in the Indian regulatory context referenced). If your ambition is to build a professional pilot career (which is part of answering How Is a CPL Different from a PPL) you'll need to prepare for the higher commitment in time cost and training level.