Q.Thyme Is Dying And Turning Brown, What Do I Do?
This is my first time growing thyme and after a few day’s my thyme plant looked dead with some green leaves growing from the center. Is it overwatered, too dry, bad soil? I’ve included pictures of before and after. And I did trim away a lot of the dead thyme.

Certified GKH Gardening Expert
It is likely your soil. Thyme requires poor soil, with very little nutrients, and dry conditions. Nutrients that are too concentrated, or soils that have too much nutrients can cause this.
Here is an article that will help you to care for the plant:
https://www.gardeningknowhow.com/edible/herbs/thyme/tips-for-growing-thyme-in-your-garden.htm