You can buy bitcoin anytime you want, and if you really want that to happen then you should start searching for a way to buy bitcoin. Buying bitcoin varies on every country, so if there's a restriction on your place then you must know that. If you're still doubt then I suggest to buy on top exchange like binance and transfer your bitcoin to a hard wallet and keep your private keys safe always. You must need to put extra effort on this, you are planning to buy at least 1 bitcoin, that's not a small amount of money.