This topic has been a long-time "friend" of mine.
But the more study put down to understand Nirvana the less is understood
Let it go said a monk to me, He did not mean letting go of Nirvana. He meant to let go of the Nirvana that i was so desperately seeking to gain. But you don't gain Nirvana, it is realized, and it is realized as to be not a place we go, we do not enter Nirvana, we become Nirvana
But not as an ego/self. Self has long been realized to be of no use so it has been let go of.
Some say Nirvana is bliss, ask them what is bliss.
Nirvana is always there for you to realize, then when realized it was always within
So look within, search to empty attachments from within.
And yes to realize it one have to let go of it, let go of Nirvana to realize it