The leverage is changeable at NF. You can even change it after you open the account if you wish. 1:200 is a good starting point for a beginner.

The thing you really should be worrying about is your starting capital. If you are thinking anything less than US$2000 is ok on NF, maybe you should be thinking of using InterbankFX so you can use micro lots instead. Having said that, the margin requirement is very generous on NF and a trade that might lead to a margin call on ibfx, wouldn't on NF. They just let you go until you totally wipe out the account