::
>How much ETH in gas fees to move USDC?
It uses about 66k gas, so you can multiply that with your gas price to get the amount of ETH needed. If you for example use a gas price of 20 gWei, which is approximately the going rate at the moment, then you can calculate ETH needed like this: 66 000 * 0.00000002 = 0.00132 ETH
>If I have $1000, $10,000 or $50,000 in USDC in an offline wallet, how much ETH do I need to move any of these amount to an exchange?
Amount is completely irrelevant. Moving 1 USDC will cost the same as moving 1 million USDC.
>And then how much extra ETH do I need to convert USDC into fiat?
Using a normal CEX like Binance the answer would be 0 ETH. You pay the fees in-kind usually, not using ETH. So the trading fee could for example be 0.1% of the USDC amount, depending on the exchange you use.