The United States, as the world's second-largest polluter, emitted a staggering 4.7 billion metric tonnes of carbon dioxide in 2020. During the Leaders’ Climate Summit, the US president articulated precise targets for combating climate change, notably a 50 to 52 percent reduction in net CO2 emissions from 2005 levels by 2030. Consequently, it becomes imperative to identify the pivotal factors that are driving this intensified dedication to achieving the Sustainable Development Goals (SDGs). Hence, it is vibrant to determine the basic causes propelling the intensified interest in meeting SDGs 7 and 13. From this perspective, this study explores the dynamic link between energy transition, fossil fuel energy, green innovation, and economic complexity index on CO2 emissions and ecological footprint in the United States from 1980 to 2020. The dynamic Autoregressive-Distributed Lag (ARDL) simulations and Frequency Domain Causality (FDC) techniques are applied for long-medium and short-run causal association among the variables. Our empirical evidence shows that energy transition, fossil fuel energy, and economic complexity increase CO2 emissions and ecological footprint. On the other hand, green innovation reduces CO2 emissions and ecological impact only in the long term. The pragmatic outcomes suggest that authorities should inhibit Fossil Fuel Energy, concentrate on energy transitions, and include more renewable sources in the US energy mix. The findings would assist the United States in meeting SDGs 7 and 13.