Unable to unblock system extension

I'm trying to install the 360Controller driver so I can use my xbox controllers on my MacBook. When I had tried to install it, at the end I had gotten an error saying the system extension was blocked. Normally I know how to fix this, just press Security & Privacy and etc. But, there was no option for that. It only showed me "Learn more..." and "OK". So I had no choice but to press OK. After this I tried installing it again. It didn't install like last time but it didn't show me the error. I tried going to Security & Privacy myself but I still wasn't able to unblock the system extension. Can anyone help?