Quickest way for Biden to win would be to sign an Executive Order to deport migrants within a two week detention period after crossing the border without judicial review. Any migrant screened determined to have a criminal record to be deported faster than immediately.
Any violence against a border control officer subjects the migrant to immediate deportation.
It would take political courage and demonstrate that the President intends to defend US borders and communicate to the cartels and the migrants that things have changed--and not have to wait for an election that will definitely change things.