Where can I buy Bitcoin legitimately?

My preferred method is Coinbase. Here is my referral link: Bitcoin & Ethereum Wallet.
This link sends you to a Bitcoin sign up page. (Pardon my shameless promotion)
Coinbase is an “exchange” that allows you to link your bitcoin to your traditional credit card and bank accounts, and will sell you Bitcoin directly – and allows you to sell your Bitcoins to Coinbase.
While there is nothing wrong with buying or selling Bitcoin to someone you met on-line, and consummating the transaction at a local coffee shop. That has a greater element of risk, but keep it in a public place, with lots of people around.
Coinbase is a legitimate, established exchange for certain cryptocurrencies.  Coinbase also owns the GDAX exchange, where you can trade for reduced fees.  You can transfer Bitcoin, Ethereum, and Litecoin from Coinbase to GDAX without paying any fees, and the trades are near real-time.
If you like to play games, or want to mine Bitcoin with a “Bitcoin Faucet”, Take a look at freebitcoin.  This is one of the longest running Bitcoin “faucets” on the internet.  When you sign up, you can play their lottery game or engage in browser-based mining.  This is good if you have a computer running, and you want to use some of it’s chip power to mine (not a fast way to get rich, but hey – Free Bitcoin?)  The link appears after you sign up, under the “free Bitcoin” tab.  FYI, I have been earning Bitcoin with them for a while, its fun.

Bitcoin faucets are a reward system, in the form of a website or app, that dispenses rewards in the form of a satoshi, which is a hundredth of a millionth BTC, for visitors to claim in exchange for completing a captcha or task as described by the website.

Here is a list of Faucets you can work with – Bitcoin Faucets. I have not tested them, so let me know if they work for you (send me an email).
Never ever send a website any bitcoin to “validate” or “justify” a payout; that is usually a scam.  This Article from Hackernoon talks about some specific scams and how to avoid them.
Be careful and cautious, and you will avoid the scams that plague any emerging internet sensation!
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