If my company made $820 million last year and pad ot 20 percent of earnings in dividends. My questions is by how much did my company retained earnings increase?

Dividends are paid out of retained earnings, therefore they would not increase at all. They would decrease. By the amount of the dividends. So what is 20% of earnings?

You retained earning increases 80% of the money that you made. 20% was dividends.