2011 forester ignition won't turn

Subaruguruboston still out there? This
is my neighbors car. 2011 forester x2.5
primers. He's suffering from a bit of
dementia n tried to use a house key to
start the car. Now security light is
steady illumination. Key will not turn
ignition all dash lights come on w key
in ignition headlights strong. Can hear
something humming under hood when
key in ignition. Battery shows No volts
when tested with volt meter. Assume it
is immobilizer but don't know how to
reset. Had a fob w lock unlock only
can't remember if there's a panic
button. Plz advise. Ps he won't drive it.
He just started it every couple weeks n
let's it run for a few. Initially he tolde
dead battery but then I found the
house keys in the ignition. Thank u