Nothing much you can do if you wish to withdraw bitcoin from the exchange. There is a fixed exchange fee plus the network fee which right now is very high. If the coin doesn't matter, then you can trade your coins for some other coins that has lower withdrawal fee such as BNB or dogecoin and transfer it to a wallet that you own. You can convert it to a stable coin like others suggested, but make sure to use a cheaper network like Tron. But if you still insist in holding bitcoin, then just hold the amount in the exchange. Since you can't pay the 0.0008 BTC, I am assuming that the amount of BTC you hold is very small. In that case, paying the fee doesn't make any sense at all.