EDITED with new answer for part 3
I'd say it's
a camera
When I’m around, I make you smile
we smile when our photos are taken
My powers reach a few good miles
we can take photos of things that are far away
It’s weird enough, you mentioned food
"Cheese" we all know someone who posts photos of his lunch
But more bizarre, just here you stood
we stand still to take a photo
Joy or dismay, I’m on my way
photos are always taken during important events even if they are tragic
The truth always, I will convey
a photo is just a representation of reality (unless photoshop was used)
hint 1 :
I am an object. A specific profession cannot work without me. Being a photographer without camera would be quite hard