Littleyon

Hello I want to download forge because I want to play on a server with friends and it's not allowing me to download forge on it, it keeps saying it can't be opened from identified developer then later I turned that off the be able to download it, then when it says something about being able to download it it says "the operation couldn't be completed. Unable to locate a Java Runtime." What am I supposed to do I tried turning off the javascript too and nothing is working please someone help