could I upload the 12 word private key on a different bitcoin hot wallet such as electrum and get my coins back?
Your 12 words is a seed phrase or mnemonic phrase, although I don't like calling them the later cause you should never try to memorize then as a back up. Private keys is a string of alphanumerics.
And yes, you can recover your wallet using the seed phrase
One more thing to note is that electrum can also be used for cold storage.