I suggest that you use coinbase or bitstamp to buy bitcoin
With Bitcoin you can transfer it to Binance, which is the most reliable cryptocurrency x cryptocurrency exchange (they don't receive USD deposits).
Then you will exchange BTC for any cheap alternative coin you like.

Also, I will suggest that you keep at least some of your holdings in BTC, which is the most reliable and secure cryptocurrency out here

Think about it. In this image you are trying to become a shitcoinner.