The following is from an article in Forbes.
Charles Darwin (most famous biologist)
The most famous biologist of all time was a firm believer in the Abrahamic God— though later in life he became somewhat conflicted in his views on his particular strain of Christianity, particularly struggling with the “problem of evil”, but despite this he is quoted as saying in 1879 “I have never been an atheist in the sense of denying the existence of a God.”
Isaac Newton and Albert Einstein (most famous physicists)
[Newton] was, however, definitely a theist, albeit an unconventional and radical one.
[Albert Einstein] believed that God existed, but that he was nebulous, universal, and not comprehensible to the human mind.