The interface itself becomes the device with increasing miniaturization in semiconductor spintronic devices. To obtain the interface and transport behaviors of novel low-dimensional spintronic devices, a fundamental physical understanding of the van der Waals magnetic system is highly desired. The interface and transport properties of the van der Waals magnetic heterostructure are studied systematically by combining first-principles calculations and Schrödinger-Poisson simulations. The layer in the van der Waals heterostructure possesses unique electronic and magnetic properties such as a ferromagnetic ground state, stable easy magnetization axis, high Curie temperature, and high mobility. The semiconductor to half metal transition and significantly enhanced conductivities can be realized in the van der Waals heterostructure via electrostatic doping. The sheet carrier density can effectively modulate the conduction band distribution, the average charge position, and the interfacial electric fields of the van der Waals heterostructure. The capacitance of the van der Waals heterostructure increases with the sheet carrier density under a suitable voltage range. Our results indicate that the van der Waals heterostructure is a promising material for the low-dimensional spintronic devices.