Coinbase is one of the oldest websites when it comes to wallet and exchanges, it makes it easy to buy and sell bitcoin, litecoin, ethereum, ethereum classic, Bitcoin cash and now oX and more to be added on a later time. Its all instant so as soon as you click buy you will have the amount added to your wallet. Coinbase supports multiple addresses to every kind of coin.
Changelly is one of the biggest exchanges where you send your coin to them and they pay out the other coin to your wallet that you give them. Its very easy to use changelly and it has very low exchange fees compared to most exchanges.
Localbitcoins is the biggest user markets for people to buy and sell between each other with the different payment methods like transfer with western union or paypal or what ever you want. Localbitcoins act like a middle man between you and the seller/buyer and makes it hard for scammers to scam people for its money.
Coinpayments are one of the biggest multi wallets out there and also the most used when it comes to accepting crypto on your store. Coinpayments accept more then 100 coins and tokens and is for sure a good place if you plan on collecting a lot of different coins in one place.
Cex.io is one of the new exchanges that allow you to buy bitcoin with your credit card or debit card without any problems. Cex.io also allow you to trade and sell your crypto.
Cardbit allow you to buy bitcoin with your credit and debit cards and even sell your bitcoin directly to your card. They also allow you to order a Debit mastercard where you can fill on your bitcoin and use it in stores and online. Cardbit do take you verify your self with ID and proof of address.