How to send BNB to Metamask using BinanceSmartChainMainnet from AtomicWallet

im trying to get BNB on Metamask using BinanceSmartChainMainnet from Atomic Wallet so i can use PancakeSwap for a new token. i paste my address from MetaMask and AtomicWallet ask me to check the address.

i have ETH in MetaMask(EthereumMainnet) but i cant transfer the ETH to BinanceSmartChainMainnet to convert to BNB