Taoism, like most religions, comes in various forms. Roughly, about 3 major forms:
There is philosophical Taoism, that focuses on ethics and the teachings in the Tao Te Ching.
There is polytheistic Taoism, which focuses on rites and rituals and prayer.
There is longevity Taoism, which focuses on health and fitness exercises.
I'd say Taoism has more in common with Mahayana, especially Zen, than Theravada.
Whereas, the closest religion to Theravada is Jainism, with its sramana path.