55 Cancri e is an actual exoplanet which should be around twice the size of Earth so it would be high gravity. It also is thought to be a carbon planet, meaning the role silicate takes on our world carbon does here. For example, the rocks are diamonds and the air is full of sot. As for the oceans, they're literally made of oil But what would the life be like?
I've tried looking for speculations about carbon planet life but I just get a bunch of biochemistry stuff. It's important for us to think about what life on these worlds might be like since they could be some of the first rocky planets to develop and hence life would have more than enough time to evolve.
As you can probably tell from the comments, this is really a whole bunch of questions in one. Let's start with what the plants, or broader sense the autotrophs, would be like in such an environment.