they both believe in karma and reincarnation. Karma means everything comes back in the end all your deeds affect what you do even killing a fly will affect your karma. Reincarnation is when someone dies and is reborn in a different body and mind buddhism and hinduism both believe in multiple gods.
Buddhism believes in multiple gods but one focal god buddha who was there founder they don't believe in the caste system and they believe suffering is the way to peace. Hinduism believe that there are multiple gods and there is a system of power they must follow to be reincarnated and be in a different position.
In conclusion hinduism and buddhism both have similarities and differences. Hinduism follows the caste system