Assuming you have MetaMask installed, follow these simple steps:
1) Launch MetaMask and click the “Main Ethereum Network” drop-down menu in the top-left corner.
2) Select “Custom RPC” from the list of options.
3) Enter the following URL into the “New RPC URL” field: https://bsc-dataseed.binance.
4) Click the “Save & Close” button.
5) You should now see “Binance Smart Chain” listed as one of your networks in MetaMask.
And that’s it! You’re now able to access Binance Smart Chain via MetaMask.