2fa on Electrum is a service provided by a trusted Coin. there is an option for that before you create a wallet at the beginning, but even if it's safe I don't recommend it for newbies or beginners, because when you lost that you will hard to recover back, I think it better to use an additional passphrase then 2fa.
You won't lose your coins if you lose 2FA provided by Trustedcoin for your 2FA Electrum wallet.
Two Factor Authentication (Electrum guide)
How to recover access to the bitcoins in your 2FA walletWhat is an Electrum 2FA Wallet and how does it work? (Trustedcoin guide)
This works by using Bitcoin's multi-signature functionality. An Electrum 2FA wallet uses 2-of-3 multi-signature addresses. This means two out of three keys are required to spend from these addresses.
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Because only one key is contained in your wallet (and two are required to spend) a wallet file compromise is no longer fatal. Since you retain possession of two of the three keys, you enjoy full control of your coins even if TrustedCoin were to disappear. Restoring your wallet from it's seed phrase offers you the option to disable 2FA (by storing both of your keys in the wallet file) or provision another 2nd factor device.
