There are various kinds of platforms where you could trade cryptocurrencies. I have read that Binance could be one of the best platforms because it supports a big variety of tokens and coins on its platform. You can choose Coinbase, but it does not offer trading facility in all the countries. I have also registered myself on Kucoin, but withdrawing money there could be a big headache. Kraken requires you to go through KYC (Know Your Customer) process. I think you must opt for Binance if you want to start trading, as it is quite popular and trustworthy exchange which is used by many traders.