  The investigation of $B$ meson decays to charmed and charmless hadronic final
states is a keystone of the Belle II program. Analyses of such decays provide
reliable and experimentally precise constraints on the weak interactions of
quarks. They are sensitive to effects from non-SM physics, and further our
knowledge about uncharted $b\rightarrow c$ hadronic transitions. We present new
results from combined analyses of Belle and Belle II data to determine the
quark-mixing parameter $\phi_3$ (or $\gamma$), and from the Belle II analyses
of two-body decays that are related to the determination of $\phi_2$ (or
$\alpha$). We also present recent Belle II results on branching ratios and
direct $\textit{CP}$-violating asymmetries of several $B$ decays, which result
in a competitive standard-model test based on the $K\pi$ isospin sum rule and
first observations of three new $B \rightarrow D^{(*)} K K_S^0$ decays.
