How to feel very happy in my life
You should not aim to be happy all the time. That shouldn't be your goal. Aim for a meaning in life instead. Aim for creating good and value in the world.
You will meet some tragedies in life for sure. You have to focus on something than can ballance whese tragedies. Find a purpose in life that gives you meaning.
However, sometimes we might add a little bit of hapiness to our lives by focusing on good things around us. As a famous philospher Seneca once sad,
"It is not the man who has too little, but the man who craves more, that is poor."
being happy or not is just state of mind, being happy not cost more than a thought, there are couple of reason around you to become a happy, one of them is you are alive ( where people died at every alternate day without reason or without mistake like, terrorism and etc )
How can I feel very happy in my life?
It can be difficult if one is a human being living on this earth to feel "very happy," but in order to be more content, I think it helps if we have some ways of feeling useful, some ways of relaxing, and some ways of connecting to others.