How do i reprogram a robot chip?R2-D2?

I am new to robotics and am really interested in it. I have an old Hasbro R2-D2 and would like to reprogram it to do new things as my first project. The main chip is numbered "mm74hc4051n" and below it is "mc74hc4051n." My questions- 1.what tools do i need to reprogram it 2. what software program do i need. Any help is appreciated as i am new to this