  Superconducting fluxonium qubits provide a promising alternative to transmons
on the path toward large-scale superconductor-based quantum computing due to
their better coherence and larger anharmonicity. A major challenge for
multi-qubit fluxonium devices is the experimental demonstration of a scalable
crosstalk-free multi-qubit architecture with high fidelity single-qubit and
two-qubit gates, single-shot readout and state initialization. Here, we present
a two-qubit fluxonium-based quantum processor with a tunable coupler element
following our theoretical proposal [DOI: 10.1063/5.0064800]. We experimentally
demonstrate fSim-type and controlled-Z gates with $99.55\%$ and $99.23\%$
fidelities, respectively. The residual ZZ interaction is suppressed down to the
few kHz level. Using a galvanically coupled flux control line, we implement
high fidelity single-qubit gates and ground state initialization with a single
arbitrary waveform generator channel per qubit.
