Will Gon ever get Nen back?

After expending the entirety of his aura, Gon is reverted back to his pre-Nen state — still physically powerful but unable to tap into his aura. Ging also warns that trying to get his power back could incur an even heavier price than what he’s already paid.

Where does Gon go end?

Gon has currently returned to Whale Island after Killua’s sister Alluka/Nanika reset his nen to the inactive state in order to heal the side effect’s caused by the contract he made to gain the power to defeat Neferpitou.