There are a few things that you need to make clear here.
First of all, what exactly do you want to do? Are you looking to buy Bitcoin and sell it at a higher price to make profit?
You say that you want to buy Bitcoin and then send it to an exchange. Why don't you buy it from the exchange directly instead and avoid the huge transaction fees?

You should carefully investigate the market before making any decisions because you might end up with a loss. I'd simply just buy Bitcoin and hold for the long-term.