If you do not want to be deceived, it's best to buy bitcoin on the stock exchange. Here is the top of the stock exchanges, all of them are large and well-tested:
-Binance
-YoBit
-EXMO
-Poloniex
-Bitfinex
-Bittrex

If you have difficulties using the exchange, you can buy bitcoin in online exchangers, there is a huge number of online exchangers, and in most countries there are already physical exchangers. But know this less safely than buying on the stock exchange