This research aimed to: (1) develop a chatbot to support information provision and assistance for first-year undergraduate students at Rajamangala University of Technology Lanna, Nan Campus; (2) evaluate the effectiveness of the developed chatbot as assessed by experts in chatbot technology and student support information; and (3) examine user satisfaction and the perceived benefits of the chatbot among first-year undergraduate students at Rajamangala University of Technology Lanna, Nan Campus. The chatbot was developed using Microsoft Copilot Studio integrated with Retrieval-Augmented Generation (RAG) and connected to the LINE application. The effectiveness evaluation was conducted by five information technology experts, while user satisfaction was assessed among 63 first-year undergraduate students. Data collection began with a needs assessment survey of second- to fourth-year students, followed by the compilation of official information from the Academic Affairs Office to design the chatbot content. The findings indicated that the chatbot was successfully developed and could be practically implemented through LINE. Expert evaluation showed that the overall effectiveness of the chatbot was at a high level, with a mean score of 4.08, with the highest ratings given to interface design and ease of use. In addition, first-year students reported high levels of satisfaction with the chatbot, with a mean score of 4.36, particularly in terms of convenience, response speed, and ease of access to information. These results demonstrate that the chatbot effectively supports communication and information services for students.