The Super Bowl will be shown for free on Fox Sports on Sunday.
Until Sunday, Fox Sports is not free. Sometimes you will get a free preview but this is normally a subscription channel and you need tv provider credentials to access (an account). Fox Sports is waiving this account requirement for the Super Bowl event only.
Until then, you will not be able to watch anything on Fox Sports for free (other than a free preview once every 24hrs) unless you have an account.
You can consider trying one of the cable-alternatives listed in the previous link that are offering free trials (youtubeTV, fubo, etc) that carry Fox Sports and Fox, and then cancel before your free trial period ends. That gives you a backup plan and alternate avenues to watch.
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