A scientist follows the scientific method, i.e. they advance testable hypotheses and compare their predictions with the data. A philosopher writes deep-sounding but ultimately meaningless drivel like this:
It's not lost on me that Tractatus was warmly received by philosophers, but Investigations got a frostier reception from the same group. I especially enjoyed Russell's snippy quote. Ol Ludwig struck a nerve, did he, Bert?
> How do you believe the results you are getting? What makes such a belief justified?
Read David Deutsch "The Fabric of Reality" chapter 7.
> What is the nature of consciousness?
Read Daniel Dennett, "Consciousness Explained".
> What are things beautiful? What makes something ascetically pleasing.
Read Richard Dawkins, "The Selfish Gene" (and, if you want to get deep into these weeds, "The Extended Phenotype").
> Why any of this exists at all?
What makes you think that any of this does exist at all?
> What is the purpose of this existence?
What makes you think that this existence has a purpose?
> Is something ethical? Science can provide answer about consequences of an action but cannot determine if said action is moral or ethical.
Read "The Evolution of Cooperation" by Robert Axelrod. (The Selfish Gene addresses this as well.)
> science is not a book of facts.
That's true.
> It is merely a process for testing a hypothesis.
No, it's not "merely" that. It is a process for producing good explanations that account for observations. That turns out to be tremendously powerful.
> It is not a replacement for philosophy, it is underpinned by philosophy.
No, it isn't. The existence of philosophy (and philosophers!) can be explained by science.