Question

write a essay in greatness of freedom

Answer 1

Spirit is free. You are a Spirit, therefore it's in your nature to be completely free, at least at some point in time.

Freedom "gives" happiness because the state of being free is aligned with your true nature. The more you are aligned with your true nature, the more you are well. When you are completely aligned with your true nature, you are completely well, and completely free.

 The importance of freedom is therefore intrinsic, but it's also subjective: you are only able to value it, as far as you can acknowledge how much it's important to you. 

The question mentions the duality of "happiness vs/or freedom", possibly implying that sometimes it's either one or the other. But, it's really not that way. This is actually a spiritual question. All beings seek true freedom and true happiness. One and the other. Brother and sister, husband and wife, twins.

There are many things that are source of (actual) happiness, and (actual) freedom is one of them.