There are some details here:
Republicans allege that Biden’s son Hunter has profited in business dealings with foreign entities by arranging access to then-Vice President Biden. They also allege that the president himself has profited.
Separately, they also say that the Justice Department interfered with investigations into Hunter Biden’s taxes. U.S. Special Counsel David Weiss, who is leading that investigation, denies that charge.
So nothing, really, but it’s the same old boring nothing. Supposedly Hunter Biden got a lot of money by granting people in foreign countries access to his dad, and then split it with Joe. Basically, they are saying Hunter did what Jared Kushner is actually on record doing for the Saudis, except there is no evidence anything happened, unlike what is publicly known about what Kushner did (and was never investigated for, as far as I know).
Also, the fact that Hunter wasn’t given the death penalty or at least life in prison for a couple of misdemeanor charges, one involving a non-payment of taxes he admitted to and eventually paid, and another for a gun possession charge that is rarely ever prosecuted but Hunter got nailed for anyway. Well, that can’t stand, Hunter needs to pay, as the first step in bringing down the Biden Crime Family that is totally not something Donald Trump made up as a desperate deflection from his family’s own misdeeds.