as a newbie, i don't know where to buy bitcoin and trade it from, i hope you can help me 
There are many of the exchange you can able to use which are good as far as I know.
kindly open this link as your reference to choose on which exchange platform you are going to use to
buy Bitcoin https://coinmarketcap.com/rankings/exchanges/ you have 20 choices here which are belong
to top 20 exchange in the market.