When arriving from AMS you should be allowed to proceed straight to the departure level.
After leaving the aircraft there is a point where the aerobridge splits into 2; you take the right lane and walk upwards and ending in the departures hall. If the right lane is blocked/non-accessible and you have to take the left lane, you will end up at arrival level and need to clear boarding pass check and security before being allowed to take the escalators up to departure level).