Hi Marcia, you do not say from where you are flying, but this should not make any difference anyway. I am sure there are far more experienced users of AMS that will be able to give more details, but here's what I can offer.

Firstly, most intra-european flight are operated on a 'seats at check-in' basis. However, KLM may be able to give you the Alitaia boarding pass at your departure city.

Secondly, Amsterdam Schiphol is, in my opinion, a very easy airport to get around, as it is a 1 terminal system. The gates are arranged in spurs from the main terminal so don't expect to be walking for more than 10-15 minutes. Your bags should be checked through to FCO, and therefore there is no customs to clear in AMS. You will not have immigration until FCO either, although there will almost certainly be some sort of passport check in AMS.