Is there any economical way to obtain my Fathers birth certificate from Warsaw?
In the absence of any information about when your father was born, you may wish to review the answers to Looking for 1901 birth/baptismal certificate in Poland?
For people whose civil acts (birth/death/marriage certificates) are available in the current government systems (and if talking about a father of a living person, you most definitely expect them to be available), obtaining them is free of charge for the immediate family. You might need to cover postage costs.
Unfortunately, all the forms and correspondence are required to be in Polish, so you'll need to pay someone to translate for you, if you don't know the language.