I think you’ve already gotten the answer you deserve from the first two replies but adding to it is that you should always add two factor authentication to every thing including buying and selling of your coins and I wouldn’t want to mention names but I think Paxful(DYOR) is a nice place to get your coins including buying and selling without much stress as their entire process seems simple and they also offer some sort of escrow to make sure the funds are secure.

If you’re in Nigeria, I also offer a private exchange and I also help to make the process easier since I also offer some sort of private exchange and if you have gift card, I also accept all country gift cards and send you bitcoin.