Or obey the law. He intentionally kept classified documents. He refused to turn them over despite being repeatedly asked to return them.
He lied about the documents. He shared some of the documents with other people, apparently. The FBI isn't responsible for the indictment.. A grand jury assessed the evidence--as compiled by the special prosecutor---and made the decision to indict. The FBI merely collected the documents.
Trump's corrupt and deeply dishonest, and has always thought he was above the law. No one is above the law.