My kids dad has 4 kids with me and says he has 11 more out there (only 1 I know about)and says he legaly don't have to pay support in Indiana if I take him to court because he has too many kids is this true

In a word - no. Child support is awarded in the order it's granted by the Court. If your petition for support is awarded first, you would get a larger percentage.

It's not how many children he has that counts, it's how many he supports (by Court Order).

Trying to lie to you to fool you into not filing.

File and get an order against him. He might not be able to pay now but at some point he may be able to pay. If he actually does have that many children he is being irresponsible.