Hi,
>:(I'm new but I'm looking trusted site to buy. Please help me.

Thanks
Before you go into online exchanges search for you local exchange in your country as I'm sure you have one and maybe even Bitcoin ATM's so in this way you can pass all the KYC stuff. I personally use my local exchange from my country whenever I want to buy cryptocurrencies and they also have partnership with SMith&Smith for sell/buy Bitcoin and Ethereum.
If you don't have one then try Binance , Coinbase and the best one in my opinion is Bitstamp...there is always the option lof localbitcoins website.