Do wall clocks specify am & pm or do you just look outside to tell if it's dark or light out?

Most don't specify, but some do especially digital clocks.

You just look outside or base it upon when you woke up

I knock on my next-door Nabours door and ask them if it's day or night.

NO THEY DO NOT BUT EVERYONE KNOWS BY DAYLIGHT..

it's the opposite in Australia

Wall clocks in my home do not specify either one. I just know which one it it.

Analog clocks usually have 12 hours, but it's easy to know whether you're in AM or PM due to our daily schedules.

Strangely enough, I look outside.

My wall clock displays digital military time.

I guess it depends on the clock.  They also make 24-hour clocks.  I personally prefer using 24-hour time.