The search for cosmic neutrino sources has intensified after the discovery of a high-energy diffuse neutrino flux. Track detection signatures from muon neutrinos are promising in pinpointing neutrino sources due to their excellent angular resolution. Cascade signatures have an inferior angular resolution, but can still contribute in discovering new sources. The KM3NeT/ARCA detector is currently under construction in the Mediterranean sea and will reach an angular resolution below degrees for cascade events. This contribution covers the cascade reconstruction performance and the neutrino event selection using the cascade channel. The previous sensitivity estimates using the track channel are extended with the cascade channel in order to improve the KM3NeT/ARCA sensitivity for diffuse and point-like neutrino sources.