My planet is a Super Earth about twice the mass of Earth. I'm not asking how it formed, although that would be nice to know. I mostly just want to know how long it would stay a torus shape, and how it would affect other other objects(including life on the surface, if habitable).
It can't exist and it can't support life.
Such a thing would have to be constructed in space. It would not produce any gravity unless it was spinning, and then only on the inside. With just rock holding it together, it would quickly fly apart and break up into asteroids floating in space. Then, over a few million years, they would crash back into each other and begin to form a proper planet.
For any of this to work, you would need magic, or it would have to be artificial.
I would recommend you checkout this video on the topic made by the channel Artifexion Artifexian - If planets were donuts. Send him son love and tell him I sent you ;)
To summarise the video: The interior equator would be extremely rugged and mountainous. The planet would have to spin at incredible speeds to keep it’s donut-goodness which in turn will cause incredible storms spun up by the planets rotation. Their would be volcanic hotspots around the pols, so polar rings of fire (that’s metal;). A moon could orbit through the hole in the planet but would likely cause a collapse of the planet, so a plain boring equatorial orbit would be most likely. And gravity would vary on the planet just as a cutaway would be egg-shaped rather then round.