I have a cold storage where I installed BTC-Electrum and LTC-Electrum wallets. So I have took extended master public keys and have generating addresses in my online service. Now I want to generate addresses for Ethereum but how can I understood the electrum core doesnt give xpub. So I need to use any wallets like MetaMask or MyEtherWallet. But I can not found how can I took xpub from those wallets.Can somebody help me to solve this problem? Thanks!
Ethereum doesn't necessarily have a concept of
xpub, but rather they use a private/public key pair.
To achieve what you want, go on a service like MyCrypto, click "Create Wallet" and follow those steps. This will generate you a private key, which you can use for your interactions with the Ethereum blockchain.