The Lunar Gateway is an essential element of deep space infrastructure that provides a multi-purpose long-duration cislunar platform. As such, it also provides an opportunity for Mars-forward use and technology development. Building on an analysis of NASA's Moon to Mars (M2M) Program objectives, architecture documentation, and Gateway's existing capabilities and requirements, this paper will recommend ways to utilize the Gateway as a testbed for future missions and operational concepts, and hardware to fill gaps in enabling future human Mars exploration. Areas of assessment include extending human life, enhancing quality of life on deep space missions, establishing a sustainable cislunar ecosystem, international partnership and commercial opportunities around the Moon. This paper is a condensed version of the final report produced by the Lunar Gateway Team Project for the International Space University’s Space Studies Program 2024. It aims to define the Gateway's role in advancing capabilities for sustainable lunar exploration while serving as a springboard for future missions to Mars. The results of this study will advise recommendations to NASA's Gateway Program on leveraging the lunar outpost for Mars and beyond.