Enter the maket

HI Professionals

I am intersted in entering the gambling market. For that reason I am developing a software which contains mainly entertaining games with the opportunety to win money. In that concern I am wondering if a gambling licens is realy necessary since the player is supposed to pay for the entertainment.
If it is necessary I would like to learn more about gambling licens, especially which are acknowleged and cheap.
I am a afraid to obtain a sublicens from a software developer because of copying my idea. Is that reasonable?

thx
Jubo