Can congress withhold or withdraw funding for Attorney General Barr and the DOJ if they begin probing into the origins of the Trump / Russia narrative?

Attorney General William Barr will look into the origins of the Christopher Steele dossier and its use to obtain FISA warrants to surveil the Trump campaign. Many Americans want to know how all this Russia collusion narrative got started.

My question is, isn’t all the mostly Democrat congress has to do in order for these investigations to cease, is to simply de-fund the Department of Justice and William Barr?