Legion Go FPS mode

Hey, I recently got a Legion Go, and I typically play on controller (both on ps5 and on PC) but I'm having a hard time using the controllers on the Legion Go for some reason (Not sure if Aim Assist is entirely turned off for the handheld, but I feel like I can't aim at all.) 

I wanna get to using the FPS mode, but I can't seem to find a layout that works for me, has anyone else been playing this in FPS mode on a Legion Go? And how did you layout the controls?