He can only run again in 2024 if he loses this time. If he loses this time, and justice is done, he’ll be facing a few criminal indictments and maybe (fingers crossed) end up in prison. While it’s not illegal to run for president from prison or while on trial for major crimes, I don’t like his chances.
Yes, but those agents are still under the command of the actual POTUS. Furthermore, the Secret Service will not protect an ex POTUS from official executive agents or officers executing a lawful search, seizure, or arrest. If the FBI, the IRS, the USPS, the state of New York, etc. want to have a field day with Trump once he’s out of office, the Secret Service won’t protect him.