While walking, you see a plant that is small, green, and growing close to the ground. When you look more closely, you see it has a very flexible stem and leaf-like structures that lack veins. You are most likely observing a(n):

You are most likely observing a moss.

Explanation:

In the Bryophyta Land Plant group the non-vascular plant species named as mosses, which are short means and herbaceous or non-woody plants that consume water and nutrients primarily form their leaves and generate carbon dioxide and sunlight for photosynthesis for food production.

They vary in absence of moisture-bearing xylem tracheids or vessels from the vascular plants. As with liverwords and hornworts, the haploid stage of gametophytes is the dominant step of the development cycle. This is in comparison to the trend in all vascular plants like seed plants and pteridophytes, where the production of diploid sporophytes is dominant. Mosses reproduce with spores, not seeds and don't have flowers.