I have a Coinbase.com account which needs only an Email and Password to sign in, but I haven't used it in over three years.
Back then, I bought $20 worth of ETH (which I traded for Privatix -PRIX- which went to $0),
so I do now still have the 42-character ETH wallet ID, but that's the only "secret" number that I have.
(Coinbase does show me the Value of that ETH ID number, at $0.)
I do not have any 12-word-seed-phrase for that.
Did I ever have a 12-word-seed-phrase for that (that I've now lost)? Is That my Wallet?
Coinbase.com is a custodial wallet, which means you don't own the private keys. They only way of accessing it is through email address and password
The 12-word-seed-phrase is not available for this type of wallet
OR does that 12-word-seed-phrase Only come with a Wallet, which is a different thing?
Coinbase has 2 products that can act as a wallet
coinbase.com, which is custodial
and coinbase wallet (
https://wallet.coinbase.com) which is noncustodial. The latter lets you back up the 12 word seed phrase, but I am pretty sure the type of the account you have is from the custodial coinbase wallet.
Now, to get back into crypto trading, do I need to also get a Coinbase Wallet, in addition to the Coinbase account?
I would suggest you to use a noncustodial wallet to keep your coins like coinbase wallet, though you can still store them in the coinbase account alone, but it's not safe since you don't own the private keys.
Not your keys, not your money