You'll have to use a Newton external modem and dial up connection if you're trying to get it on the internet but there's really no point, virtually no current website would load or display properly.
I used a modem and an app called Newtscape to connect to the internet with my MP120 ~20 years ago and it was pretty useless even then.
Any Newton MP other than a 2000 or 2100 is really only useful as a display piece.