Python 3.13 removed deprecated functions to configure Python initialization, such as Py_SetPath(), and there is no replacement API for the limited C API: the PyConfig API (PEP 587) is excluded from the stable ABI because of the big PyConfig structure which is has no ABI guarantees.
A new API is being designed/discussed in the FR: Allow private runtime config to enable extending without breaking the `PyConfig` ABI topic and my PyInitConfig API PR. A PEP may be written for that.