Swapping my ethereum (ethereum mainnet) for BNB (smart chain) on my metamask

does anyone know how to swap ethereum (ethereum mainnet) to BNB (smart chain) on metamask?
I’ve been really struggling to find the answers. They say you can do it on Binance but I dont see the option.

I plan to trade my ETH for BNB so I can start using pancake swap.

I’ve come across binance dot org (link below) and looks like it would accomplish exactly what I want. But wasn’t if its legit or recommenced. because nobody brings it up.

If anyone can help in great detail that would be great.