am i able to port foward on the motorola SB5101 modem?

[boungst]

im trying to setup a vpn on a raspberry pi and i need to be able to set up port fowarding on my motorola SB5101 modem...

im new to all of this i dont really know how any of this works yet

i have my motorola SB5101 modem flashed with haxorware connected to a apple airport extreme basestation router

can anyone help me out?