How do use proclaim in a sentence?

Use it when you use a quote. For example:

"One day I will be a free man out on my own," the man proclaimed.

proclaim (verb): to declare, to inform, or to make known.

Present Action - "I proclaim the good news to all people."

Past Action - "The Word was proclaimed throughout the world."

Continuous Action - "He has been proclaiming the same message for years."