All of life can be traced back to living things that harness energy from light and that is plants that use photosynthesis for energy. Photosynthesis works because there is a free source of energy raining down on our planet: the Sun.
Therefore, when looking for alien life, it is safe to assume it would also harness power from its star. But how exactly would it do that?
Well, it would all depend on the strength of its star and the nature of its atmosphere. Therefore plants on other planets could look very different from here on Earth.
YouTuber It's Okay To Be Smart explains all this in great detail with some pretty nifty illustrations. If you have ever wondered about alien plant life, this is the video for you!