Akismet uses your wordpress.com account to register the Key
So if you have an account there, that’s the login.
When you are creating an account, click on the “I already have a wordpress .com account” at the top of the form. (blue letters just below the title.)
It will then take you to a place to sign in, rather than create an account.
here you will find “forgot your password?” below the form to the right.
Then just follow the steps to get your account info, then head back and sign in to register the Akismet API Key.
Just a heads up: Akismet is not free. For a one-site plan, I think it is 5 bucks a month.
There are some free ones out there in the wordpress plugin database.
For example
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