Buying a large amount of BTC is not an issue nowadays, but you better watch where you do it.
Localbitcoins will be one option if you do not want to go through the hassle of creating an account with an exchange site,
but it will take some time to find the number of people who are trusted, can offer you bigger amounts and are willing to trade with you
as a newbie.
Another option is to open an exchange account with a trusted exchange, like coinbase or bitstamp, but it will take some time
to go through their verification processes, like ID verification, etc. The advantage is that once you have this, you are basically set, and
the fees to buy/sell are much lower than anywhere else.
good luck