The former naval officer said he would never forget heading out on his first ship, the HMAS Sydney, at the age of 17 after joining the defence force in 1965.
"It was exciting to be going out to sea," the Vietnam War veteran said.
"It wasn't until many decades later we were to learn the health consequences of our service."
Mr Manolas, the Naval Association of Australia's president, will commemorate the service and sacrifice of his fellow veterans as the navy celebrates its 125th anniversary this year.
"We do what we can to support navy veterans so that they may be settled back into civilian life," he said.
The Exercise Kakadu Fleet Review in March was the largest gathering of international warships on Sydney Harbour in more than a decade, and marked the foundation of Australia's navy.
Up to 30 ships from 19 countries participated in the event.
Retiring from full-time service in 2001, Mr Manolas said he was envious of today's young sailors and officers as the navy acquired new capabilities, including the promised nuclear-powered submarines under the AUKUS agreement.
"As I've come to meet them, they have so much enthusiasm and there is a great deal of opportunity and so much the navy can offer them in a successful career," he said.
"Everything is rapidly changing and that has always been the case. There's never been a situation where things have been stagnant."
On the significance of Anzac Day, Mr Manolas urged the public to visit the Australian War Memorial in Canberra to reflect on the sacrifices made by servicemen and women.
"It is an opportunity for us to give thanks and we encourage those to make their way to the streets of the city in observance and commemoration of the service gone before," he said.
"Whether we are more mature or younger in age, we must never lose sight of that privilege."