How do I erase autofill

I am assuming you are referring to the AutoFill feature in Safari which pulls information from a variety of sources. You can delete, make changes, and set preferences for this feature. To view these preferences, choose Safari > Preferences, then click AutoFill.

This article provides additional information on each of the settings:

Safari AutoFill preferences on Mac - Apple Support

If you provide additional information about why you want to erase everything, and exactly what 'everything' someone on this discussion thread may be able to provide additional suggestions. Are you seeing incorrect information populate when using AutoFill? What type of information?

I can’t seem to find where auto fill is getting an old phone number of mine. I’m my contacts the correct phone number appears but I can’t get it to stop suggesting the old number.

Also my contacts seem to be defaulting to “home” instead of “mobile” or “iPhone” as I entered them. Where do I go to change these things?