Now is not the time to buy, it's only just gone up again after the big drop a couple of months ago. I have 4k in Eth, which has gone up and down over the past 8 months, I missed the high because it crashed overnight, so I have waited for it to rise again. This is where I learned a lot. I now have 70k sat in limbo, waiting for a drop / dip.
The platform I use is called Kraken. It's very solid. Easy to use, but the setting up of the account is time consuming, but for good reason. The security is rock solid, so if you're going to det up an account, make sure you save all of your passwords etc offline and FFS don't lose them. It's very hard to get back in without them if you forget them.