Solana Rent Exemption Question

According to the solana docs

Alternatively, an account can be made entirely exempt from rent collection by depositing at least 2 years worth of rent.

Does that mean after two years, the rent in the account has been deposited would never be needed and always be free from then on? Thanks for reply:)

Does it support in withdrawing all lamports for emptying the account? If supported, will the address/account be continued to be available?

Could someone help?