Chiral hybrid organic inorganic perovskites combine the structural handedness of chiral organic cations with the strong spin orbit coupling of heavy metal halide layers. This makes them promising materials for chiral spintronics, where an electric field or strain, rather than a magnetic field, controls the electron spin. Two questions remain open: whether the electric polarization in these crystals can be switched, and whether switching the polarization also switches their spin textures. Answering them requires atomistic modelling that experiments alone cannot provide. In this project we use first-principles density functional theory (DFT) to study the experimentally reported polar and non-polar chiral two dimensional halide perovskites A2BX4 (B = Pb, Sn; X = Cl, Br, I), together with their enantiomers and halide-substituted analogues. We compute the spontaneous polarization with the Berry-phase method, identify the symmetry-breaking distortions behind it through symmetry-mode analysis and Landau theory, and determine polarization-reversal pathways and energy barriers with nudged-elastic-band calculations. Including spin–orbit coupling, we map the momentum-space spin textures and fit them to symmetry-adapted k·p spin Hamiltonians, which separates Rashba, Dresselhaus, radial and persistent contributions. We then examine how shear strain and layer sliding tune the polarization and spin splitting, and how chirality and the choice of organic cation set the sign and size of the spin–orbit fields. Switching in real samples involves thermal motion of the organic cations over long times and large length scales. We therefore combine ab initio molecular dynamics with machine-learned interatomic potentials trained on our DFT data. These potentials allow finite-temperature simulations of polarization switching in supercells of tens of thousands of atoms. The project will deliver design rules that connect molecular chirality, crystal symmetry and halide composition to switchable polarization and spin texture, and will identify the most promising compounds for experimental validation. The work is carried out at the Division of Materials Theory, Uppsala University, and the results will be published in peer-reviewed journals.