I have an E-Max E8 controller from an RTF Kit I bought 2 years ago and I still use it as my Sim controller on the Mac. And I recently bought a used Armattan Chameleon. I managed to bind the two together (or at least that's what I know cause the receiver led is green) but I cannot arm it or control it. I tried to connect the drone to betaflight but I'm totally clueless about it. Does the controller and receiver are even compatible? Please some one help me, I would love to fly my first ever 5 inch drone.

if you get solid green light it should work.

bf configurator - choose the right uart in ports tab and select serial rx
go into receivertab and set sbus as receiver protocoll.