Gaining precise control over quantum systems is crucial for applications in quantum information processing and quantum sensing and to perform experimental tests of quantum mechanics. The experiments presented in this thesis implement quantum measurements and real-time feedback protocols that can help to achieve these goals using single electron and nuclear spins associated with the Nitrogen Vacancy (NV) center in diamond. Here we demonstrate that adaptive measurements allow for the manipulation of a quantum system using only measurement backaction and that they can enhance the performance of a single spin magnetometer. Furthermore, by creating entanglement and performing teleportation between two distant NV centers, we implement two elementary operations between two nodes of a quantum network.