I want to start business of buying cattle, but I don't know where or what to do, and am new in this business industry, can you please help further?

Go to school, college preferably, and take some agricultural business courses, along with a course or two on beef cattle production, cattle pricing, beef economics, and similar things. To start earning money, work at a livestock auction where you get to see and work with the various kinds of animals that come in, and learn as much as you can there. You will need to spend money to learn in order to make money being a cattle buyer, and start from the bottom in order to get to the top. Talk to a few livestock market sales people to see how and where they got to where they are and see if they have any tips for you!