No, they can’t. People claiming it’s a possibility are letting their partisanship overwhelm their reason or scholarship. The Founding Fathers were very clear that they thought a criminal indictment against a sitting President was problematic to say the least. The mechanism of impeachment is purely to remove said Chief Executive. It’s not a criminal trial, although it should use the same standards of evidence. If said person is out of office, impeachment is irrelevant and invalid.
I think the Dems are going down this road to besmirch Trump because they know they’d lose in court if they tried actual criminal charges. With impeachment, they can have a standard-less kangaroo court like they did the first time around. We’ve already seen Kamala has no compunction about using the legal system against people she knew were innocent.