to the extent that there's some valid concern underlying the question regarding whether democrats are able to reach what they call independents, unaligned voters, low information voters and generally unpolitical citizens, you can't undo the 10 years of targeting these people that trump has invested in with an hour of time.
further, the entire point is that trump is not kamala harris and kamala harris is kamala harris, in the sense that she's an establishment politician. these voters or non-voters are simply not politically aligned with the kamala harrises of the world, they are politically aligned directly against the kamala harrises, and she would have little chance of swinging them.
what that suggests is that if the democrats want to access these voters, and they no doubt should, that they should be running candidates that appeal to them, which would be somebody like bernie sanders and not somebody like kamala harris.
the next democratic primary will probably be very open and a candidate that appeals to non-voters will have a better chance.
democrats need to understand that kamala harris was a bad candidate that couldn't win and that the only tactic the party has is to stop running bad candidates that can't win. there is nothing she could have done differently besides not running in the first place.