The charge transfer cross sections of collisions between He ions in the solar wind and H₂O molecule constitute essential data required for the astrophysical plasma modeling. However, experimental measurements of single charge transfer (SCT) cross sections for He⁺-H₂O collisions at low-to-intermediate energies (corresponding to the velocity range of the solar wind) are extremely scarce, and first-priciple theoretical calculations have not been conducted. In this study, employing the time-dependent density functional theory nonadiabatically coupled with the molecular dynamics, the SCT cross sections are calculated for He⁺-H₂O collisions over a broad energy range of 1.33–1800 keV. An inverse collision framework is used to investigate the charge transfer dynamics and electron-ion coupling processes. It is found that the SCT cross section exhibits a strong dependence on the molecular orientation. Furthermore, there are significant differences in the contributions of different molecular orientations to the cross section between low-energy and high-energy regions. The computed cross section results show good agreement with the existing data obtained from experiments and classical theoretical models. This indicates that the present theoretical method and numerical framework are not only applicable to handling the charge transfer processes in collisions between dressed ions and molecules but also enable the quantitative analysis of the effect of molecular orientation on the cross section. This study lays a foundation for cross section calculations of complex collision systems. The datasets presented in this paper are openly available at https://doi.org/10.57760/sciencedb.j00213.00193.