Hinduism as it exists today didn't exist in the Buddha's time. There were sects of Brahmans who practiced varied ritual folk religions with contradicting belief

Hinduism as it exists today didn't exist in the Buddha's time. There were sects of Brahmans who practiced varied ritual folk religions with contradicting beliefs and ideas. Actually, at the time of the Buddha, there was a lot of debate between Brahman clans about what happens after death. There were arguments for reincarnation, which Buddhism clarifies as rebirth without an eternal soul, as well as for eternalism (ie you go to heaven forever if you're good) and annihilationism (ie you die and that's it, no more existence), both of which the Buddha explicitly refuted.