When I started rendering an animation it kept using 1 frame for every frame and sometimes it renders blank as well. I am rendering on cycles, but it is also rendering instantly and when I put it on eevee it goes on cycles quality.
Most likely this is because you have an image sequence/single image in the video editing tab of Blender. Simply delete this strip, and your animation should render correctly.
This would explain the black frames, repeated frames, instant renders, and cycles-quality renders when set on EEVEE.