I need to reset an old Macbook

I have an old macbook computer it is not a pro or air it is just a macbook. I have been trying to reset the computer for days and it is not working I do not have an installation disk for it so i tried shutting down the computer and upon restarting it i held down COMMAND + R as well as OPTION + S . something called disk utility is supposed to pop up but it does not. it takes me through the set up process as if the mac is brand new out of the box it asks me to select my language and my keyboard language then it asks me to set up the administrator, once i go through that whole process of putting in my name and my apple i.d the computer should restart or keep proceeding with the set up but it does not it goes back to the initial set up and asks for all that information again... please does anyone know why the computer is doing this how do i finish the set up so that I can actually use the computer.... the picture attached is what I'm talking about after filling out that page it goes back to the begining telling me pick language , pick keyboard language setup wifi then back to create computer account page.