Bacteria.
Plants evolved before animals.
They don't.
Non-seed plants evolved from seed plants.
No, all life evolves. Bacteria evolve, viruses evolve, protists evolve, plants evolve, fungi evolve and animals evolve. Evolution is driven by Natural Selection. So, no. The evolution of all life on Earth is driven by Natural Selection: all bacteria, plants, animals, mammals, fish, insects, biochemical pathways, behaviours et cetera evolve by Natural Selection.
green algae
In the Mesozoic Era, during the cretaceous period
Nonvascular plants
No. Flowering plants emerged around 140 million years ago.
One of the first land plants to evolve was likely green algae, which transitioned from aquatic environments to terrestrial habitats around 450 million years ago. These plants laid the foundation for the development of more complex land plants such as mosses and ferns.
Precambrian
The plants and animals must evolve. They are also part of the biotic factors in an ecosystem.
The first plants to evolve on Earth were likely simple, non-vascular plants like algae that appeared around 1 billion years ago. These early plants eventually gave rise to more complex vascular plants, like ferns and seed-producing plants, through the process of evolution over millions of years.