What can i do to come and live in Germany

To live in Germany as a non-EU-citizen you need a valid residence visa.
The most common such visa are for work (you need to find a job first!) or family reunion (you need to be married to a German citizen or long-term resident), but there are also others, e.g. for asylum seekers.
Maybe you can contact your nearest German embassy to find out which one is applicable for your situation.
Once you have a residence visa, your (minor) kids can join as dependants.

Must i have to be married to live in Germany ? what if i rent a house a have sufficient savings can i  cant ask for a  5 year residence card.?

I am afraid there is no visa type for that. But please consult the embassy, they might know a way!
In any case residence visa usually have to be renewed yearly.