Yes I think evolution is a theory.
A good scientist knows other theories may come and change the landscape. So you need to keep an open mind.
That's why I posted the link to the theory of the deep fountains. I think it's a good theory explaining some events in the past.
Is it true? I don't know. But we also have no proof for evolution. But the theory of evolution works very well to explain a lot.
The only science that has proof is math.
(I'm not a creationist by the way)