PS4 Controller settings

Hi everyone! Having recently moved form Overwatch into apex, i’m having some difficulties adjusting to the foreign movement based playstyle of apex legends. I have realised that it’s practically impossible to have crouch on its default button, given the nature of this game https://vidmate.onl/ . Any suggestions for button layouts and ADS sens? Also, can someone pls tell me how to build momentum quickly in order to slide on the ground with little ground space? I see youtubers and other players sliding in point blank range, seemingly from crouch to a slide immediately. Can’t wrap my head around it..