Jean,
As previously mentioned you only need to own (1) share to receive a dividend, there is no minimum. Dividends are profit distributed to the shareholders(owners) of the company.
Declaration date - the company's management will announce they are paying a dividend, the amount, when it will be paid, and the ex-dividend date.
Ex-dividend date - Existing shareholders will receive the dividend. If you buy a share of this company after this date, you will not receive the dividend. If you sell your stock after this date, you will still receive the dividend.
Payment date - You will receive the dividend.
To determine how much in dividends the companies pay I would first look at what the company declares and what they've paid in the past. You can also use a stock screener and screen for dividend yield >0%. That will list companies that give you a dividend. Then you multiply the Dividend Yield by the stock price for the yearly dividend amount. Then divide that by 4 and that's what the quarterly dividend would be.