This qualitative study investigated the perceptions of prospective teachers on critical thinking (CT) skills before and after completing the Functional English (FE) course at the Bachelor of Education Honors (B.Ed. Hons) and Associate Degree in Education (ADE). A purposive sampling technique was employed to select 40 participants, with eight allocated to each of the five focus group discussions from two universities and three teacher education colleges in the Hazara Division, located in the Khyber Pakhtunkhwa Province of Pakistan. Additionally, five unstructured classroom observations took place within these five institutions. Semi-structured questions guided the focus group discussions, while unstructured observation techniques were employed for data collection. The findings from the thematic analysis indicated a significant shift in prospective teachers' perspectives regarding enhancing CT skills before and after completing the FE course. Prospective teachers recognized the significance and impact of inquiry in fostering CT skills. Furthermore, they identified the importance of diverse resources within the context of learning and student-centered classrooms in developing CT skills. The field notes from unstructured observation witnessed CT skills during participant-led open classroom discussions. The study suggests promoting prospective teachers' engagement in analytical thinking and applying these skills to real-world challenges, including the subject matter taught, the content's source and credibility, and the intricate connections between newly acquired information and prior knowledge.