The paper conducts an empirical comparative study on cybersecurity awareness, behaviours, and attitudes of residents from urban, rural, and semi-urban areas in the Coimbatore District, Tamil Nadu, India. Following a quantitative cross-sectional survey research approach, a dataset was generated from 392 participants recruited by means of a stratified random sample. The main instrument of measurement utilized for the study was the Cybersecurity Awareness Inventory (CAIN). Security behaviour measures and threat awareness attitudes were also included based on standardized psychometric scales. Statistical analysis of data consisted of simple percentages, weighted average calculations, and one-way ANOVA. Important insights obtained include an alarming level of knowledge gap since despite the majority of respondents (more than 75%) being aware of cybersecurity to some extent, over 54% proved to be "Not Aware" according to the knowledge-based objective assessment. It is worth mentioning that there was no significant difference in cybersecurity practice scores among residents from urban, rural, and semi-urban settings (p = 0.500). In other words, location became irrelevant as far as safe online behaviour is concerned. On the other hand, age, occupation, and education appeared to have a considerable impact on awareness and behaviour scores. The threats that participants could recognize best included phishing attacks and identity theft, while the technically complicated DoS attacks were less recognized. The results indicate that there is a need for cybersecurity campaigns targeting particular age groups, such as older people and salaried employees, using multiple languages. This research is in sync with SDG 4 (Quality Education), SDG 10 (Reduced Inequalities), and SDG 16 (Peace, Justice, and Strong Institutions) and suggests interventions that are specific, multilingual, and institution-based to close the cyber-security knowledge-doing gap.