First of all, do not trust anyone. Because you have the wallet on your computer, do not let anyone have access to it. I mean do not let anyone have access to your computer.
You can setup a 2FA wallet and have the 2FA app on another device. But you may not like it because of addictional fee and because you do not have the thrid private key.
You can prefer to go for cold storage wallet,
https://electrum.readthedocs.io/en/latest/coldstorage.htmlYou can even get a hardware wallet like Trezor and use it with Electrum wallet.
You may even prefer to setup a multisig wallet, but which will require more than one device.
Use a strong password.
Backup your seed phrase in a safe location. For better security, you can use passphrase along with it, but backup the passphrase in a different location. If you lose your passphrase or seed phrase, you will lose your coins.
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