I don't have much experience with paper wallets but you will eventually have to move any BTC you would like to withdraw to Gemini. Simply get the BTC receive address from Gemini and send your BTC to Gemini. Once you have your BTC on Gemini, sell to USD and then withdraw the USD from Gemini via Bank Transfer (make sure you have your bank account linked to Gemini). Via bank transfer, it takes 2-3 business days for your USD to show up in your bank account. Thanks @daydreams4rock!