The rapid advancement of wireless communication technologies has led to an increasing demand for more efficient and intelligent communication systems. Reconfigurable Intelligent Surfaces (RIS) have emerged as a promising solution to address the challenges of future wireless networks, such as high spectral efficiency, low latency, and enhanced coverage. RIS, based on configurable metamaterials, can manipulate the propagation of electromagnetic waves by adjusting the phase or amplitude of wireless signals, thereby creating programmable wireless environments. This technology has the potential to revolutionize the way we design and optimize communication systems. Accurate channel modeling and simulation are crucial for evaluating the performance of RIS in various scenarios and for guiding the development of RIS-related technologies. As one of the key technologies for future 6G networks, significant efforts have been made to develop channel models that can capture the unique characteristics of RIS-assisted communication links. This white paper aims to provide a comprehensive overview of the channel modeling and simulation work for RIS, highlighting the latest research findings and offering insights for future research directions. By presenting detailed channel models, system-level simulation results, and discussions on key technical issues, this paper seeks to contribute to the ongoing standardization efforts and promote the development and application of RIS technologies in future wireless communication systems.