How can one overcome the disbelief-inducing waswas (whispers) that resurfaced after hearing about Darwin's theory and attempts to create living organisms, and how can one draw closer to God again after having drifted away? And with what can the opposite of this theory be proven?

Darwin's theory is nonsense that contradicts explicit verses from the Book of Allah. As for the problems of obsessive-compulsive disorder, its treatment lies in ignoring it, seeking refuge in Allah, frequent remembrance of Allah (dhikr), avoiding solitude and mixing with deviant people, befriending good people, diverting one's mind from thinking about it, along with consistent ruqyah (definition) (Islamic exorcism/healing), occupying one's mind and heart with beneficial knowledge or fruitful work such as worship, social service, or charitable activity, and staying away from the company of bad people.