Radiative and electroweak penguin mediated decays of $B$ mesons are a great probe for physics beyond the Standard Model of particle physics. Furthermore, recently anomalies on exclusive $b\to s\ell^+\ell^-$ processes which may imply lepton flavor universality violation, have been observed. Belle II experiment sheds light on the anomalies with the measurement of an inclusive analysis in this mode. Thanks to smaller hadronic uncertainties compared with exclusive modes, complementary information can be provided. Belle II is also a unique experiment to search for processes involving neutrinos such as $B\to K^{(*)}\nu\bar{\nu}$. We report the results and prospects of an inclusive $B\to X_s \ell^+\ell^-$ analysis and a search for $B\to K^{(*)}\nu\bar{\nu}$.