If you are interacting on the Binance Smart Chain you will need BNB in order to pay for the transaction costs (gas)
Adding BNB Into Metamask
PLATFORMS AND EXCHANGES
Buying Crypto For Trade Below are the best options for buying crypto to trade.
Binance or Binance US (this is the easiest way to get BNB)
Create a free account | Binance.US
Kucoin: (if you are in USA & unable to get Binance you may need another platform to use with this such as Coinbase)
KuCoin | Cryptocurrency Exchange | Buy & Sell Bitcoin, Ethereum, and More
How to buy BNB with Kucoin-
Coinbase- There are 2 versions of Coinbase. Regular & Pro.
Regular is easier to navigate early on and the Pro version is a bit more complicated but has less trading fees. You can onboard your fiat through regular to get started then start migrating over to Pro when you get the hang of things.