We know what Donald Trump did: He absconded from the White House with classified and top secret documents that belonged to the US government; he mishandled these highly sensitive records in his Mar-a-Largo lair (see this photo); he resisted the efforts of the government to retrieve these records; he employed a legal team that falsely certified that all classified material had been returned; and his actions prompted the Justice Department to investigate whether he and his crew obstructed justice or violated other federal laws, including the Espionage Act.
https://www.motherjones.com/politics/2022/08/trump-stole-classified-documents-mar-a-lago-the-big-question-is-why/