how is used differential port in diffrential LNA

Hi,
I don't know how i can use port (in cadence) in differential LNA and also, what resistance should i use in output of differential buffer? ( i mean that 50 Ω or 25 Ω because of two branches)

it depends on per port impedance.
if per port impedance is 50 ohm then use 100ohm as termination resistance