Is there any effective technique for us to live a happy life with no worries at all?
One strategy is to cut out the activities, people and situations that cause stress and worry. I've done that to a degree and am happy. If you are not happy, step back and look at the big picture and why you are not happy. Then set about making changes to cut the culprits out of your life, or find ways to distract yourself away from things you can't change. That is my strategy anyway.