1998 Subaru Impreza boost gauge

Engine Mechanical problem
1998 Subaru Impreza 4 cyl All Wheel Drive Manual

HI

Ive had a subaru impreza before same year and reg ( r) on old car started enginge and boost gauge went to 0, which im sure is wright, as my mate has boost gauge.

NOW when I tried to connect to the pressure outlet, thats a spare 1, blocked off. It reads! - 0.5 HELP.

what can I do so it reads like it should. When I start. 0.