There are many ways to withdraw from Hive. It's different for every country so you might want to ask other people from your country what is the most reputable place for exchanging crypto for fiat.

Once you find an exchange, you send your Hive to them by following their deposit instructions. If they don't accept Hive, you may have to convert the Hive to BTC or LTC or some other coin. You can use something like blocktrades or simpleswap or tribaldex to convert Hive into other coins.

But please understand that Hive is not a charity website. People like me don't vote for people who are always powering down and selling all of their rewards. For your vote to have any value, you have to power up your Hive. Why would I vote for your posts if you will sell all of your rewards and your vote will never have any value? I have a limited number of votes and I'd rather vote for people who will power up.

If you give your neighbor seeds to grow food, but he sells the seeds instead of planting them, do you keep giving him seeds? Or do you give the seeds to someone who wants to grow?