Question about FRITZ! Box 7580

How can I operate the FB 7580 in bridge mode? I am a newcomer to FB. I would like to operate it in bridge mode in front of my Unifi USG 4 Pro. I have now changed to green.ch and they think it should work, but I can't find the bridge mode switch :-) where do I change it? I have the 7580 with OS 7.02 (I think). Thanks for feedback