Can anyone explain to me how to be part of the stock market?

i have money, i don’t know how to buy a stock. i only see them in the newspaper. what qualifications do i need to have, to participate in the stock market? next, whats your usual procedure when buying a stock? lastly, what do you need to know to know when to buy or sell a stock or how to have a good decision? what does one need to know or need to observe when they already bought a stock?