This study investigates the influence of ChatGPT on critical thinking and English language learning within Ukrainian university English departments. Utilizing qualitative and quantitative methods, it involved 31 students and three language instructors in surveys and ChatGPT-assisted project-based activities. The significance of this study lies in its potential to guide the integration of AI tools in educational contexts, particularly in language learning. By examining the benefits and challenges of using ChatGPT, the study provides insights into how AI can support or hinder language learning and critical thinking. This is particularly relevant in the context of rapidly evolving educational technologies and the increasing use of AI in academic settings. In the spring semester of 2023, a research study was carried out involving students participating in a project-based activity using ChatGPT. The study comprised two main phases: initial survey, project completion, and evaluation. Quantitatively, it was found that 62% of students use ChatGPT weekly, underlining its role in their language studies. The results showed varied perspectives on its efficacy, especially in critical thinking, English skills development, and ethical considerations. Ethical and pedagogical issues were also significant, including concerns about the authenticity of AI responses, plagiarism risks, and AI dependency. Nevertheless, the potential advantages of ChatGPT, such as immediate language support and the promotion of learner independence, were acknowledged by students. The research concludes by recommending a careful integration of AI in language education.