Use a temporary, disposable, free email:
https://www.guerrillamail.com/
Recently, every time I use this, they have "disabled sending email for today". Which makes it useless.
The whole point of a temporary email address is so you can give it to a spam site, they send you an questioning email to verify that you gave them a valid email address, then you reply to their email to give the verification.
But there are a ton of other temporary/free email address providers. Just do a Google search.