I am surrounded by uplifting, supportive people who believe in me.

It's rarely the whole floor. Usually it is two people, and often not the two anybody would predict — someone from a different department who asks how the thing went, and a colleague you have almost nothing in common with who reliably notices when you have gone quiet.

Belief at work tends to be practical rather than stated. It sounds like being handed something difficult, or being asked to sit in on a meeting you were not required at.

Nobody declares it. Being asked is the declaration.