The present study was an attempt to help us reveal the characteristics and complexity of today’s first-time online students in a higher education setting. Data were collected from undergraduate and graduate students enrolled in fully online courses for the first time during spring semester in the 2016–2017 academic year at a Southern university in the United States. Primarily, path analysis was conducted to investigate the impacts of flexible thinking, mindsets, and self-efficacy on the 254 first-time online students’ online learning engagement. The results of the path analysis supported six out of the eight hypotheses and all standardized path coefficients have values between 0.14 and 0.31. In conclusion, growth mindset and learning self-efficacy appear to be important variables for first-time online students and have a positive relation to online engagement. The practical implications and future research are discussed.